Exhibit 99

15985 East High Street

P. O. Box 35

Middlefield, Ohio 44062

Phone: 440/632-1666 FAX: 440/632-1700

www.middlefieldbank.com

PRESS RELEASE

Middlefield Banc Corp. Reports 2015 Full Year and Fourth Quarter Financial Results

MIDDLEFIELD, OHIO, January 27, 2016 ¿¿¿¿ Middlefield Banc Corp. (NASDAQ: MBCN) today reported financial results for the fourth quarter and full year ended December 31, 2015.

2015 Fourth Quarter Financial Highlights Include (on a year-over-year basis unless noted):

“We ended 2015 with record assets and loans outstanding, and experienced higher year-over-year net interest income and noninterest income. As expected, noninterest expenses increased at a faster rate as we invested in our business to support our growth plan. During the year, we opened a new Loan Production Office in Mentor, Ohio, and added a number of new senior lenders and managers to our leadership team. We have a strong infrastructure in place that is focused on executing our growth oriented business plan. I am encouraged with our loan growth in the fourth quarter, which was up 4.6% from the third quarter and 13.7% from the same period last year. Our markets remain strong and we expect 2016 will be another good year for Middlefield,” stated Thomas G. Caldwell, President and Chief Executive Officer.

Net income for the 2015 fourth quarter was $1.8 million, or $0.92 per diluted share, compared to $1.9 million, or $0.92 per diluted share for the same period last year. Net income for the 2015 full year was $6.9 million, or $3.39 per diluted share, compared to net income for the year ended December 31, 2014 of $7.2 million, or $3.50 per diluted share.

Annualized returns on average equity (“ROE”) and average assets (“ROA”) for the 2015 fourth quarter were 11.26% and 0.96%, respectively, compared with 11.98% and 1.10% for the 2014 fourth quarter. ROE and ROA were 10.62% and 0.97%, respectively, for the 2015 full year, compared with 12.17% and 1.07% for the same period last year.

Mr. Caldwell continued: “During 2015, we made a lot of progress executing our strategic plan and significantly improved the company’s infrastructure to support a larger organization. 2016 will benefit from the full year contribution of our new lenders, business managers and Mentor LPO, and we are optimistic this will drive higher assets and loans. In addition, we expect a greater contribution from our secondary mortgage program in 2016 as we improve our execution and enhance customers’ awareness of this offering. Overall, we are focused on strategies that grow Middlefield’s brand across all of our markets. Fundamental to our growth plan is our community banking approach aimed at supporting the financial needs of our communities.”

Income Statement

Net interest income for the 2015 fourth quarter increased 5.0% to $6.4 million, compared to $6.1 million for the 2014 fourth quarter. For 2015, net interest income increased 4.1% to $24.8 million, compared to $23.8 million for 2014. The fourth quarter and twelve month increases in net interest income were driven by an increase in interest and fees and a reduction in funding costs. The net interest margin for the 2015 fourth quarter was 3.89%, compared to 3.91% for the same period of 2014. For 2015, the net interest margin was 3.94%, compared to 3.93% for the twelve months ended December 31, 2014.

Noninterest income was up 14.8% for the 2015 fourth quarter and 12.7% for the 2015 twelve months. The improvement to noninterest income in the 2015 fourth quarter was primarily a result of investment gains and earnings on bank-owned life insurance. For 2015, gains on the sale of loans in addition to the increase in investment gains and earnings on bank-owned life insurance contributed to the full year improvement.

Noninterest expense for the 2015 fourth quarter was $5.4 million, an increase of 16.0% from $4.6 million for the 2014 fourth quarter, primarily a result of higher operating expenses. For the full year, noninterest expenses increased 12.5% to $20.1 million, from $17.9 million in 2014.

“We experienced strong asset and loan growth in 2015, while maintaining high quality lending practices,” said Donald L. Stacy, Chief Financial Officer. “The ratio of nonperforming loans to total loans was 1.92% at the end of the 2015 fourth quarter, consistent with the prior year period, while nonperforming assets to total assets declined 13 basis points to 1.59%. We did a good job managing our cost of funds in 2015, which experienced a seven basis point reduction to 0.72% from 0.79% in 2014. The yield on earnings assets declined modestly representing the competitive nature of our markets. Noninterest expense increased 12.5% for 2015 as we made strategic investments in our operations and added personnel. While we continue to expect higher regulatory, compliance and technology costs to remain, we are focused on leveraging 2015’s operating investments in 2016.”

Balance Sheet

Total assets at December 31, 2015 increased 8.5% to $735.1 million, from $677.5 million at December 31, 2014. Net loans at December 31, 2015 were $527.3 million, compared to $463.7 million at December 31, 2014. The 13.7% year-over-year improvement in net loans was a result of a 21.8% increase in commercial and industrial loans, a 10.7% increase in residential mortgages, a 21.5% increase in commercial mortgages, and a 6.1% increase in consumer installment loans, which were offset by a 26.9% reduction in real estate construction loans.

Total deposits at December 31, 2015 increased 6.5% to $624.4 million from $586.1 million at December 31, 2014. The investment portfolio, which is entirely classified as available for sale, stood at $146.5 million at December 31, 2015, compared to $154.3 million at December 31, 2014.

Stockholders’ Equity and Dividends

Tangible stockholders’ equity decreased to $57.7 million for the 2015 fourth quarter, compared to $59.2 million at December 31, 2014, as a result of the company’s October 2, 2016 repurchase of 196,635 shares of its common stock. On a per share basis, tangible stockholders’ equity increased 6.5% to $30.72 at December 31, 2015 from $28.84 at December 31, 2014. At December 31, 2015, the company had equity to assets of 8.48%, compared to 9.43% at December 31, 2014.

During the 2015 fourth quarter, the company paid cash dividends of $0.27 per share, which was a 3.8% increase over the amount paid in the 2014 fourth quarter. For 2015, the company paid total dividends of $1.07 per share, which represents a dividend payout ratio of 30.90%, compared to dividends of $1.04 and a dividend payout ratio of 29.54% for the 2014 full year.

Asset Quality

The provision for loan losses for the 2015 fourth quarter was $0.1 million, compared $0 for the 2014 fourth quarter. For 2015, the provision for loan losses was $0.3 million, compared to $0.4 million for the same period last year. Net charge-offs for the 2015 twelve months were $0.8 million, or 0.16% of average loans, annualized. The allowance for loan losses at December 31, 2015 stood at $6.4 million, or 1.20% of total loans, compared to $6.8 million or 1.45% of total loans at December 31, 2014.

The following table provides a summary of asset quality and reserve coverage ratios.

Middlefield Banc Corp., headquartered in Middlefield, Ohio, is a bank holding company with total assets of $735.1 million at December 31, 2015. The bank operates 10 full service banking centers and an LPL Financial^® brokerage office serving Chardon, Cortland, Dublin, Garrettsville, Mantua, Middlefield, Newbury, Orwell, and Westerville. The Bank also operates a Loan Production Office in Mentor, Ohio. Additional information is available at www.middlefieldbank.com.

This press release of Middlefield Banc Corp. and the reports Middlefield Banc Corp. files with the Securities and Exchange Commission often contain “forward-looking statements” relating to present or future trends or factors affecting the banking industry and, specifically, the financial operations, markets and products of Middlefield Banc Corp. These forward-looking

statements involve certain risks and uncertainties. There are a number of important factors that could cause Middlefield Banc Corp.’s future results to differ materially from historical performance or projected performance. These factors include, but are not limited to: (1) a significant increase in competitive pressures among financial institutions; (2) changes in the interest rate environment that may reduce interest margins; (3) changes in prepayment speeds, charge-offs and loan loss provisions; (4) less favorable than expected general economic conditions; (5) legislative or regulatory changes that may adversely affect businesses in which Middlefield Banc Corp. is engaged; (6) technological issues which may adversely affect Middlefield Banc Corp.’s financial operations or customers; (7) changes in the securities markets; or (8) risk factors mentioned in the reports and registration statements Middlefield Banc Corp. files with the Securities and Exchange Commission. Middlefield Banc Corp. undertakes no obligation to release revisions to these forward-looking statements or to reflect events or circumstances after the date of this press release.

MIDDLEFIELD BANC CORP.

Consolidated Selected Financial Highlights

December 31, 2015 and 2014

MIDDLEFIELD BANC CORP.

Consolidated Selected Financial Highlights

December 31, 2015 and 2014

(Dollar amounts in thousands)

(2015 unaudited)