Exhibit 99.1

IMMEDIATE RELEASE

Graham Corporation Reports

Fiscal 2017 Third Quarter Results

BATAVIA, NY, February 1, 2017 – Graham Corporation (NYSE: GHM), a global business that designs, manufactures and sells critical equipment for the oil refining, petrochemical, power and defense industries, today reported financial results for its third quarter and nine months ended December 31, 2016. Graham’s current fiscal year ends March 31, 2017 (“fiscal 2017”).

Net sales in the third quarter were $22.7 million, compared with net sales of $17.3 million in the third quarter of the fiscal year ended March 31, 2016 (“fiscal 2016”). Net income in the third quarter was $1.8 million, or $0.19 per diluted share, compared with $1.3 million, or $0.13 per diluted share, in the prior-year third quarter.

James R. Lines, Graham’s President and Chief Executive Officer, commented, “Our diversification strategies positively impacted the third quarter results, with approximately one-third of our sales coming from the U.S. Navy and nuclear power markets. Additionally, our gross margin in the quarter was significantly and favorably impacted by conversion of a non-typical order. Our diversification into markets not directly correlated to energy has certainly benefited recent performance and is expected to drive long-term growth.”

Third Quarter Fiscal 2017 Sales Review

(See accompanying financial tables for a breakdown of sales by industry and region)

Sales growth was favorably impacted by execution of a large non-typical order received in the second quarter of fiscal 2017. Additionally, sales to the power market were up to $4.4 million compared with $2.7 million in the third quarter of fiscal 2016. Ongoing weakness in the global energy markets is expected to continue to impact Graham’s traditional refining and chemical/petrochemical businesses for the remainder of fiscal 2017. From a geographic perspective, sales to the U.S. were significantly higher than the prior-year third quarter, while sales to most international markets were down.

Fluctuations in Graham’s sales among geographic locations and industries can vary measurably from quarter-to-quarter based on the timing and magnitude of projects. Graham does not believe that such quarter-to-quarter fluctuations are indicative of business trends, which it believes are more apparent on a trailing twelve month basis.

Graham Corporation Reports Fiscal 2017 Third Quarter Results

February 1, 2017

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Third Quarter Fiscal 2017 Operating Performance Review

Third quarter gross profit and margin significantly benefited from a large non-typical order that began converting in the quarter. The prior-year third quarter was hampered by a very unfavorable mix of projects which were converted.

Selling, general and administrative (“SG&A”) expenses increased 2% to $3.8 million. SG&A as a percent of sales was 17% in the third quarter of fiscal 2017 compared with 22% in the same prior-year period.

Operating profit in the prior-year third quarter benefited from $1.8 million of other income resulting from cancellation charges that were negotiated and settled with customers in that period.

During the third quarter of fiscal 2017, Graham had an effective tax rate of 29%. The effective tax rate in the third quarter of fiscal 2016 was 22%, which was favorably impacted by the U.S. government’s retroactive reinstatement of the federal research and development tax credit during the Company’s fiscal third quarter 2016.

To summarize, the increase in net income in the third quarter of fiscal 2017 reflects higher revenue and improved gross margin, offset by the impact of cancellation charges recorded in last year’s quarter and a lower effective tax rate in last year’s quarter.

The comparison of Adjusted EBITDA (consolidated net income before interest expense and income, income taxes, depreciation and amortization and a nonrecurring restructuring charge where applicable) was impacted by similar factors:

Graham believes that, when used in conjunction with measures prepared in accordance with GAAP, Adjusted EBITDA and Adjusted EBITDA margin (Adjusted EBITDA as a percentage of sales), which are non-GAAP measures, help in the understanding of its operating performance. Graham’s credit facility also contains ratios based on EBITDA. See the attached tables for additional important disclosures regarding Graham’s use of Adjusted EBITDA and Adjusted EBITDA margin as well as a reconciliation of net income to Adjusted EBITDA.

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Graham Corporation Reports Fiscal 2017 Third Quarter Results

February 1, 2017

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First Nine Months Fiscal 2017 Review

International sales of $17.0 million in the first nine months of fiscal 2017 represented 26% of total sales, compared with $24.0 million, or 35% of sales, in the same prior-year period. Sales to the U.S. were $49.1 million, or 74%, of net first nine months sales in fiscal 2017 compared with $43.7 million, or 65%, of fiscal 2016 first nine months net sales.

The decrease in the fiscal 2017 first nine months gross margin reflects lower pricing due to the deteriorating market conditions experienced over the past two years.

SG&A in the fiscal 2017 first nine months was $10.6 million, $2 million, or 16%, lower than the prior-year period. As a percent of sales, SG&A was 16% in the first nine months of fiscal 2017 compared with 19% in the same prior-year period. This improvement reflects lower commissions, lower compensation costs and other actions taken to reduce costs, as well as the benefit of insurance proceeds recorded in the second quarter of fiscal 2017.

Operating profit and margin were impacted by the above factors as well as the inclusion of a $0.6 million restructuring charge in fiscal 2017 and the $1.8 million cancellation charge income noted above as realized in fiscal 2016.

Excluding a $0.4 million net of tax, nonrecurring restructuring charge recorded in the first nine months of fiscal 2017, adjusted net income, a non-GAAP number, was $3.7 million or $0.38 per diluted share. Graham believes that, when used in conjunction with measures prepared in accordance with GAAP, adjusted net income helps in the understanding of its operating performance. See the attached tables for additional important disclosures regarding Graham’s use of adjusted net income as well as a reconciliation of GAAP net income to non-GAAP adjusted net income.

The comparison of Adjusted EBITDA reflects similar factors:

See the attached tables for additional important disclosures regarding Graham’s use of Adjusted EBITDA and Adjusted EBITDA margin as well as a reconciliation of net income to Adjusted EBITDA.

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Graham Corporation Reports Fiscal 2017 Third Quarter Results

February 1, 2017

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Balance Sheet Strengthens

Cash, cash equivalents and investments at December 31, 2016 were $72.7 million, up $7.6 million from the end of fiscal 2016. The balance at December 31 reflects strong customer deposits that are expected to unwind over the next couple of quarters.

Cash provided by operations in the first nine months of fiscal 2017 was $10.7 million, compared with $22.2 million in the first nine months of fiscal 2016. The reduction was primarily due to lower net income in fiscal 2017 year-to-date as well as unusually high cash flow from working capital in the prior-year period.

Capital expenditures were $0.2 million in the first nine months compared with $0.9 million in the same prior-year period. The Company expects capital expenditures for fiscal 2017 to be approximately $0.5 million for the full year. Capital investments are expected to be used for equipment upgrades and productivity enhancements.

Dividend payments were $2.6 million for the first nine months of fiscal 2017, slightly higher than $2.4 million in the prior-year first nine months.

Graham had neither borrowings under its credit facility, nor any long-term debt outstanding, at December 31, 2016.

Backlog Continues to Demonstrate Success of Diversification Strategy

Backlog at the end of the fiscal 2017 first nine months was $99.1 million, down $4.9 million sequentially from the end of the fiscal 2017 second quarter due to continued weakness within the energy markets.

The Company’s backlog mix by industry continues to highlight the success of its diversification strategy to increase sales to the U.S. Navy and the power industry. Backlog by industry at December 31, 2016 was approximately:

The expected timing for that backlog to convert to sales is as follows:

Orders in the third quarter of $17.7 million were down 21% from $22.3 million in the same prior-year period, as the order climate remains volatile. Orders from U.S. customers were $10.4 million, or 59%, and orders from international markets were $7.3 million, or 41%, in the third quarter of fiscal 2017. During the fiscal 2017 third quarter, an order for $0.4 million which had been on hold was moved into active status. At December 31, 2016 two refining orders in backlog valued at $6.5 million remain on hold.

Orders for the first nine months of fiscal 2017 were $57.1 million, compared with $66.8 million in the first nine months of fiscal 2016. Orders from U.S. customers were $39.4 million, or 69%, and orders from international markets were $17.7 million, or 31%, in the first nine months of fiscal 2017. This compares with 55% U.S. and 45% international in the first nine months of fiscal 2016.

Graham expects that the balance between domestic and international orders will continue to be variable between quarters.

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Graham Corporation Reports Fiscal 2017 Third Quarter Results

February 1, 2017

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FY 2017 Guidance Update and Outlook

Mr. Lines stated, “As we enter the fourth quarter of our fiscal year, we have clearer visibility into our expected full year performance. Accordingly, we’ve tightened our revenue expectations within our prior range. Our gross margin and SG&A guidance are unchanged and we lowered our tax rate guidance. Looking forward, we anticipate SG&A at a quarterly run rate of approximately $4 million.”

Graham is updating its fiscal 2017 guidance, as follows:

Mr. Lines concluded, “There are positive qualitative indications within our energy markets that improvement is underway, however, it has not yet translated into quantitative improvement in the number or quality of bidding opportunities. We expect that improvement will materialize in due course, consistent with normal energy cycle performance.”

Webcast and Conference Call

Graham’s management will host a conference call and live webcast today at 11:00 a.m. Eastern Time to review Graham’s financial condition and operating results for the fiscal 2017 third quarter, as well as its strategy and outlook. The review will be accompanied by a slide presentation which will be made available immediately prior to the conference call on Graham’s website at www.graham-mfg.com under the heading “Investor Relations.” A question-and-answer session will follow the formal presentation.

Graham’s conference call can be accessed by calling (201) 689-8560. Alternatively, the webcast can be monitored on Graham’s website at www.graham-mfg.com under the heading “Investor Relations.”

A telephonic replay will be available from approximately 2:00 p.m. Eastern Time on the day of the call through Wednesday, February 8, 2017. To listen to the archived call, dial (412) 317-6671, and enter conference ID number 13652421. A transcript of the call will be placed on Graham’s website, once available.

ABOUT GRAHAM CORPORATION

Graham is a global business that designs, manufactures and sells critical equipment for the energy, defense and chemical/petrochemical industries. Energy markets include oil refining, cogeneration, nuclear and alternative power. For the defense industry, the Company’s equipment is used in nuclear propulsion power systems for the U.S. Navy. Graham’s global brand is built upon world-renowned engineering expertise in vacuum and heat transfer technology, responsive and flexible service and unsurpassed quality. Graham designs and manufactures custom-engineered ejectors, vacuum pumping systems, surface condensers and vacuum systems. Graham is also a leading nuclear code accredited fabrication and specialty machining company. Graham supplies components used inside reactor vessels and outside containment vessels of nuclear power facilities. Graham’s equipment can also be found in other diverse applications such as metal refining, pulp and paper processing, water heating, refrigeration, desalination, food processing, pharmaceutical, heating, ventilating and air conditioning. Graham’s reach spans the globe and its equipment is installed in facilities from North and South America to Europe, Asia, Africa and the Middle East. Graham routinely posts news and other important information on its website, www.graham-mfg.com, where additional comprehensive information on Graham Corporation and its subsidiaries can be found.

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Safe Harbor Regarding Forward Looking Statements

This news release contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended.

Forward-looking statements are subject to risks, uncertainties and assumptions and are identified by words such as “expects,” “estimates,” “confidence,” “projects,” “typically,” “outlook,” “anticipates,” “believes,” “appears,” “could,” “opportunities,” “seeking,” “plans,” “aim,” “pursuit,” and other similar words. All statements addressing operating performance, events, or developments that Graham Corporation expects or anticipates will occur in the future, including but not limited to, expected expansion and growth opportunities within its domestic and international markets, anticipated revenue, the timing of conversion of backlog to sales, market presence, profit margins, tax rates, foreign sales operations, its ability to improve cost competitiveness, customer preferences, changes in market conditions in the industries in which it operates, changes in commodities prices, the effect on its business of volatility in commodities prices, changes in general economic conditions and customer behavior, forecasts regarding the timing and scope of the economic recovery in its markets, its acquisition and growth strategy and the expected performance of Energy Steel & Supply Co. and its operations in China, are forward-looking statements. Because they are forward-looking, they should be evaluated in light of important risk factors and uncertainties. These risk factors and uncertainties are more fully described in Graham Corporation’s most recent Annual Report filed with the Securities and Exchange Commission, included under the heading entitled “Risk Factors.”

Should one or more of these risks or uncertainties materialize, or should any of Graham Corporation’s underlying assumptions prove incorrect, actual results may vary materially from those currently anticipated. In addition, undue reliance should not be placed on Graham Corporation’s forward-looking statements. Except as required by law, Graham Corporation disclaims any obligation to update or publicly announce any revisions to any of the forward-looking statements contained in this news release.

FINANCIAL TABLES FOLLOW.

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February 1, 2017

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Graham Corporation

Third Quarter Fiscal 2017

Consolidated Statements of Operations—Unaudited

(Amounts in thousands, except per share data)

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February 1, 2017

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Graham Corporation

Third Quarter Fiscal 2017

Consolidated Balance Sheets—Unaudited

(Amounts in thousands, except per share data)

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February 1, 2017

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Graham Corporation

Third Quarter Fiscal 2017

Consolidated Statements of Cash Flows—Unaudited

(Amounts in thousands)

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February 1, 2017

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Graham Corporation

Third Quarter Fiscal 2017

Adjusted Net Income Reconciliation—Unaudited

(Amounts in thousands, except per share data)

Non-GAAP Financial Measure:

Adjusted net income is defined as GAAP net income excluding a nonrecurring restructuring charge. Adjusted net income is not a measure determined in accordance with generally accepted accounting principles in the United States, commonly known as GAAP. Nevertheless, Graham believes that providing non-GAAP information such as Adjusted net income is important for investors and other readers of Graham’s financial statements, as it is used as an analytical indicator by Graham’s management to better understand operating performance. Because Adjusted net income is a non-GAAP measure and is thus susceptible to varying calculations, Adjusted net income, as presented, may not be directly comparable to other similarly titled measures used by other companies.

Graham Corporation

Third Quarter Fiscal 2017

Adjusted EBITDA Reconciliation—Unaudited

(Amounts in thousands)

Non-GAAP Financial Measure:

Adjusted EBITDA is defined as consolidated net income before interest expense and income, income taxes, depreciation and amortization and a nonrecurring restructuring charge. Adjusted EBITDA margin is Adjusted EBITDA divided by sales. Adjusted EBITDA and Adjusted EBITDA margin are not measures determined in accordance with generally accepted accounting principles in the United States, commonly known as GAAP. Nevertheless, Graham believes that providing non-GAAP information such as Adjusted EBITDA and Adjusted EBITDA margin are important for investors and other readers of Graham’s financial statements, as they are used as analytical indicators by Graham’s management to better understand operating performance. Graham’s credit facility also contains ratios based on EBITDA. Because Adjusted EBITDA and Adjusted EBITDA margin are non-GAAP measures and are thus susceptible to varying calculations, Adjusted EBITDA and Adjusted EBITDA margin, as presented, may not be directly comparable to other similarly titled measures used by other companies.

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Graham Corporation Reports Fiscal 2017 Third Quarter Results

February 1, 2017

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Graham Corporation

Third Quarter Fiscal 2017

Additional Information—Unaudited

ORDER & BACKLOG TREND

($ in millions)

SALES BY INDUSTRY FY 2017

($ in millions)

SALES BY INDUSTRY FY 2016

($ in millions)

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Graham Corporation

Third Quarter Fiscal 2017

Additional Information—Unaudited

(Continued)

SALES BY REGION FY 2017

($ in millions)

SALES BY REGION FY 2016

($ in millions)

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