EXHIBIT 99.1

For further information:
David B. Ramaker, CEO
Lori A. Gwizdala, CFO
989-839-5350

Chemical Financial Corporation Reports Second Quarter 2011 Results

MIDLAND, MI, July 25, 2011 -- -- Chemical Financial Corporation (NASDAQ:CHFC) today announced 2011 second quarter net income of $11.0 million, or $0.40 per diluted share, compared to 2011 first quarter net income of $9.2 million, or $0.33 per diluted share, and 2010 second quarter net income of $4.4 million, or $0.17 per diluted share. Net income was $20.2 million, or $0.74 per diluted share, for the six months ended June 30, 2011, compared to $6.7 million, or $0.27 per diluted share, for the six months ended June 30, 2010.

"Our earnings performance continues to trend upward as we benefit from lower loan loss provisions, lower credit related costs and sustained improvements in the credit quality of our loan portfolio. However, in terms of the economy, we are not yet witnessing the level of economic growth characteristic of previous recoveries," said David B. Ramaker, Chairman, Chief Executive Officer and President of the Company.

"While the economy is showing signs of strengthening, it is not yet able to support robust organic balance sheet growth. We continue to believe that our avenue for increased profitability and growth will result from initiatives that organically expand our market share and consolidation opportunities in Michigan's banking industry," added Ramaker.

Higher net income in the second quarter of 2011, compared to the first quarter of 2011, was primarily attributable to a lower provision for loan losses and lower operating expenses. The provision for loan losses was $0.5 million lower in the second quarter of 2011 than in the first quarter of 2011, with the decline largely attributable to a reduction in net loan charge-offs. Operating expenses were $2 million lower in the second quarter of 2011 than in the first quarter of 2011, with the reduction driven by the reversal of a state tax expense accrual, lower loan collection costs and lower FDIC premium expense. The state tax expense accrual reversal, resulting from the elimination of a contingent liability, of $1.2 million increased earnings by $0.03 per diluted share in the second quarter of 2011. The increase in net income in the second quarter of 2011 over the second quarter of 2010 was primarily attributable to a $5.7 million reduction in the provision for loan losses.

The Company's return on average assets during the second quarter of 2011 was 0.84 percent, up from 0.70 percent in the first quarter of 2011 and 0.36 percent in the second quarter of 2010. The return on average equity was 7.8 percent in the second quarter of 2011, up from 6.6 percent in the first quarter of 2011 and 3.3 percent in the second quarter of 2010.

Net interest income was $45.3 million in the second quarter of 2011, up slightly from $45.2 million in the first quarter of 2011 and up from $42.9 million in the second quarter of 2010. The net interest margin (on a tax-equivalent basis) in the second quarter of 2011 was 3.78 percent,

unchanged from 3.78 percent in the first quarter of 2011 and down from 3.88 percent in the second quarter of 2010. The increase in net interest income during the second quarter of 2011 compared to the same quarter in 2010 was primarily attributable to the acquisition of O.A.K. Financial Corporation (OAK) and its subsidiary Byron Bank on April 30, 2010.

The provision for loan losses was $7.0 million in the second quarter of 2011, compared to $7.5 million in the first quarter of 2011 and $12.7 million in the second quarter of 2010. Second quarter 2011 net loan charge-offs were $6.9 million, compared to $7.4 million in the first quarter of 2011 and $7.3 million in the second quarter of 2010.

Total noninterest income was $10.9 million in the second quarter of 2011, compared to $10.8 million in the first quarter of 2011 and $11.0 million in the second quarter of 2010. The increase in the second quarter of 2011, as compared to the first quarter of 2011, was due primarily to higher service charges on deposit accounts and wealth management revenue that were partially offset by a decline in mortgage banking revenue. Service charges on deposit accounts and wealth management revenue were $0.5 million and $0.3 million, respectively, higher in the second quarter of 2011, as compared to the first quarter of 2011, while mortgage banking revenue was $0.6 million lower.

Operating expenses were $33.4 million in the second quarter of 2011, down from $35.4 million in the first quarter of 2011 and $34.6 million in the second quarter of 2010. The decrease in operating expenses in the second quarter of 2011, as compared to the first quarter of 2011 and the second quarter of 2010, was primarily attributable to the reversal of a $1.2 million state tax expense accrual, as previously discussed. The Company had remaining contingent state tax expense accruals of approximately $0.5 million at June 30, 2011. Credit-related operating expenses were $1.4 million in the second quarter of 2011, down from $2.1 million in the first quarter of 2011 and $1.8 million in the second quarter of 2010. The Company's second quarter 2011 efficiency ratio was 58.2 percent, compared to 61.8 percent in the first quarter of 2011 and 63.1 percent in the second quarter of 2010.  

Total assets were $5.20 billion at June 30, 2011, down from $5.34 billion at March 31, 2011 and up from $5.12 billion at June 30, 2010. The decrease in assets during the second quarter of 2011, as compared to the first quarter of 2011, was largely attributable to a decrease in interest-bearing balances held at the Federal Reserve Bank (FRB). The Company continues to maintain significant amounts of funds generated from deposit growth over the last two years at the FRB, further enhancing the Company's liquidity position, with $265 million in balances held at the FRB at June 30, 2011, compared to $520 million at March 31, 2011 and $440 million at December 31, 2010. Total loans were $3.75 billion at June 30, 2011, compared to $3.68 billion at March 31, 2011 and $3.65 billion at June 30, 2010. Investment securities were $802 million at June 30, 2011, compared to $750 million at March 31, 2011 and $811 million at June 30, 2010.

Total deposits were $4.25 billion at June 30, 2011, compared to $4.38 billion at March 31, 2011 and $4.20 billion at June 30, 2010. The Company experienced a decrease of $131 million, or 3.0 percent, in total deposits during the quarter ended June 30, 2011, with the majority of the decrease attributable to a seasonal decrease in deposits and repurchase agreements of municipal customers. The Company used a portion of its liquidity to pay off maturing Federal Home Loan

Bank (FHLB) advances and brokered deposits acquired in the OAK transaction and intends to continue to pay off these wholesale funding sources as they mature. FHLB advances totaled $71.9 million at June 30, 2011, down from $72.9 million at March 31, 2011 and $86.6 million at June 30, 2010. Brokered deposits acquired in the OAK transaction totaled $110 million at June 30, 2011, compared to $151 million at March 31, 2011 and $163 million at December 31, 2010.

At June 30, 2011, the Company's tangible equity to assets ratio and total risk-based capital ratio were 8.9 percent and 13.0 percent, respectively, compared to 8.5 percent and 13.0 percent, respectively, at March 31, 2011. At June 30, 2011, the Company's book value was $20.78 per share, compared to $20.54 per share at March 31, 2011.

The credit quality of the Company's loan portfolio continues to show signs of stabilization. At June 30, 2011, the Company's originated loans, representing all loans other than those acquired in the OAK transaction, had nonaccrual loans and loans past due 90 days or more totaling $109.1 million, compared to $108.5 million at March 31, 2011 and $116.3 million at June 30, 2010. The Company's nonperforming loans also include commercial, real estate commercial and real estate residential loans that have been modified due to financial difficulties being experienced by customers (nonperforming troubled debt restructurings) of $26.8 million at June 30, 2011, compared to $37.4 million at March 31, 2011 and $26.6 million at June 30, 2010. The reduction in nonperforming troubled debt restructurings in the second quarter of 2011 resulted from the Company reclassifying $12.9 million of these loans to a performing status, as borrowers of these loans have made at least six consecutive payments under the modified loan terms.

Other real estate and repossessed assets totaled $24.6 million at June 30, 2011, compared to $26.4 million at March 31, 2011 and $21.7 million at June 30, 2010. The net decrease in the second quarter of 2011 was primarily attributable to sales of properties that were partially offset by additions of foreclosed properties during the quarter.

At June 30, 2011, the allowance for loan losses was $89.7 million, or 2.78 percent of originated loans, compared to 2.85 percent at March 31, 2011 and 2.95 percent at June 30, 2010. The allowance for loan losses as a percentage of nonperforming loans was 66 percent at June 30, 2011, compared to 61 percent at March 31, 2011 and 63 percent at June 30, 2010. At June 30, 2011, nonperforming loans as a percentage of total loans were 3.63 percent, compared to 3.96 percent at March 31, 2011 and 3.92 percent at June 30, 2010.

Chemical Financial Corporation is the second-largest bank holding company headquartered in Michigan. The Company operates through a single subsidiary bank, Chemical Bank, with 142 banking offices spread over 32 counties in the lower peninsula of Michigan. At June 30, 2011, the Company had total assets of $5.2 billion. Chemical Financial Corporation's common stock trades on The NASDAQ Stock Market under the symbol CHFC and is one of the issues comprising the NASDAQ Global Select Market. More information about the Company is available by visiting the investor relations section of its website at www.chemicalbankmi.com.

Forward-Looking Statements

This press release contains forward-looking statements that are based on management's beliefs, assumptions, current expectations, estimates and projections about the financial services industry, the economy and Chemical Financial Corporation. Words such as "continue," "trend," "yet," "signs," "will," "anticipate," "intend" and variations of such words and similar expressions are intended to identify such forward-looking statements. Such statements are based upon current beliefs and expectations and involve substantial risks and uncertainties which could cause actual results to differ materially from those expressed or implied by such forward-looking statements. These statements include, among others, statements related to the credit quality of our loan portfolio, future levels of nonperforming loans, future economic trends, future initiatives to expand our market share and future opportunities for acquisitions. All statements referencing future time periods are forward-looking. Management's determination of the provision and allowance for loan losses, the carrying value of acquired loans, goodwill, mortgage servicing rights and other real estate owned and the fair value of investment securities (including whether any impairment on any investment security is temporary or other-than-temporary and the amount of any impairment) involve judgments that are inherently forward-looking. Management's assumptions concerning pension and other postretirement benefit plans involve judgments that are inherently forward-looking. There can be no assurance that future loan losses will be limited to the amounts estimated or that other real estate owned can be sold for its carrying value or at all. The future effect of changes in the financial and credit markets and the national and regional economy on the banking industry, generally, and on the Company, specifically, are also inherently uncertain. These statements are not guarantees of future performance and involve certain risks, uncertainties and assumptions ("risk factors") that are difficult to predict with regard to timing, extent, likelihood and degree of occurrence. Therefore, actual results and outcomes may materially differ from what may be expressed or forecasted in such forward-looking statements. The Company undertakes no obligation to update, amend or clarify forward-looking statements, whether as a result of new information, future events or otherwise.

Risk factors include, but are not limited to, the risk factors described in Item 1A of the Company's Annual Report on Form 10-K for the year ended December 31, 2010. These and other factors are representative of the risk factors that may emerge and could cause a difference between an ultimate actual outcome and a preceding forward-looking statement.