Exhibit 99

15985 East High Street

P. O. Box 35

Middlefield, Ohio 44062

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

www.middlefieldbank.bank

PRESS RELEASE

Middlefield Banc Corp. Reports 2016 First Half Financial Results

MIDDLEFIELD, OHIO, July 20, 2016 ¿¿¿¿ Middlefield Banc Corp. (NASDAQ: MBCN) today reported financial results for the 2016 first-half and second quarter ended June 30, 2016.

2016 First Half Financial Highlights versus 2015 First Half:

“The significant growth we experienced for the 2016 first half reflects an excellent second quarter of increased productivity from our new lenders, business managers and the recently opened Mentor LPO,” stated Thomas G. Caldwell, President and Chief Executive Officer. “These investments in our workforce and geographic expansion, helped us grow net loans at June 30, 2016 by 17.8% compared with the same period last year, which in turn allowed us to improve our efficiency ratio from 67.79% to 65.99%.

“I am pleased to report significant improvements in profitability for the 2016 first half as net income per diluted common share increased 14.0% to $1.73 and our tangible book value increased 11.3% to $32.47 per share. Net income for the 2016 second quarter increased 28.0% to a record $1.9 million, or $0.94 per diluted share, from $1.5 million, or $0.73 per diluted share for the 2015 second quarter. We are making progress executing the strategic plan we created last year as we grow our banking footprint, and increase our market share. We remain optimistic 2016 will experience asset and loan growth, and improved profitability.”

Annualized returns on average equity (“ROE”) and average assets (“ROA”) for the 2016 six-month period were 10.62% and 0.92%, respectively, compared with 9.92% and 0.91% for the same period last year. For the 2016 second quarter returns on average equity (“ROE”) and average assets (“ROA”) were 11.78% and 1.03% respectively, compared with 9.54% and 0.85% for the 2015 second quarter.

Mr. Caldwell continued: “During the quarter, we began construction on a new branch in Sunbury, Ohio, which we expect to open in the 2016 third quarter. This will be our 11^th full-service banking location and our third office in Central Ohio. We are excited to expand our presence in Central Ohio to Delaware County, which is 20 miles north of Columbus and is the fastest growing suburban county in the State of Ohio, and the 21^st fastest in the U.S. As we grow our franchise, I am encouraged with our direction. Our two distinct Ohio markets have strong demographics and stable economies. We are working hard to grow Middlefield’s presence within our local communities, while providing our customers with a community bank that is safe, strong and committed.”

Income Statement

For the 2016 first half, net interest income increased 3.5% to $12.7 million, compared to $12.2 million for the same period last year. Year-to-date, the net interest margin was 3.82%, compared to 3.92% for the same period last year. Net interest income for the 2016 second quarter was $6.3 million, compared to $6.1 million for the 2015 second quarter. The net interest margin for the 2016 second quarter was 3.78%, compared to 3.83% for the same period of 2015. The 4.3% increase in net interest income for the 2016 second quarter was largely a result of an 8.1% increase in interest and fees on loans.

For the 2016 first half, noninterest income increased 18.4% to $2.1 million, compared to $1.8 million for the same period last year. Noninterest income for the 2016 second quarter was up 21.9% to $1.2 million primarily a result of gains on the sales of investment securities.

For the 2016 first half, noninterest expense increased 2.2% to $10.3 million, compared to $10.0 million for the same period last year. The increase in noninterest expenses were modest through the 2016 first half primarily because of a 5.8% reduction in 2016’s second quarter expenditures. Operating costs in the 2016 second quarter declined to $4.9 million from the 2015 second quarter’s $5.2 million and were down 7.9% from the 2016 first quarter.

“Our asset quality remains strong, as year-to-date net charge-offs have declined 62.1% from the same period last year,” said Donald L. Stacy, Chief Financial Officer. “The 22.0% year-over-year increase in second quarter nonperforming loans is mainly due to the 17.6% increase in our loan portfolio over this same time. Economic trends in our local communities remain stable and we continue to focus on managing risk and maintaining high quality lending practices. We had $21.1 million in cash and cash equivalents on our balance sheet at June 30, 2016 and net loans to total deposits of 91.3%. We were able to leverage the increase in noninterest expenses we experienced in the 2016 first quarter, and actually reduced operating costs sequentially and year-over-year. As a result, profitability increased significantly with strong improvements in ROA and ROE during the quarter. We expect stable profitability throughout the remainder of 2016 as we control expenses and grow our base of earning assets.”

Balance Sheet

Total assets at June 30, 2016 increased 7.7% to $760.1 million, from $705.5 million at June 30, 2015. Net loans at June 30, 2016 were $573.4 million, compared to $486.5 million at June 30, 2015. The 17.8% year-over-year increase in net loans was a result of loan growth in both residential and commercial mortgages, which increased 15.1% and 25.3%, respectively, as well as a 10.1% increase in commercial and industrial loans, partially offset by a 3.7% decline in real estate construction loans and a 17.5% decline in consumer installment loans.

Total deposits at June 30, 2016 increased 0.7% to $628.0 million from $623.5 million at June 30, 2015. The company continued to proactively manage its cost of funds and control deposit growth. The investment portfolio, which is entirely classified as available for sale, was $129.3 million June 30, 2016, compared with $157.6 million at June 30, 2015.

Stockholders’ Equity and Dividends

At June 30, 2016 tangible stockholders’ equity was $73.0 million an increase of 21.3% from $60.2 million at June 30, 2015. On a per share basis, tangible stockholders’ equity increased 11.3% to $32.47 at June 30, 2016 from $29.16 at June 30, 2015. Through the first six months of 2016, the company paid cash dividends of $0.54 per share, which was an increase of 1.9% over the same period last year. The dividend payout ratio for the 2016 six-month period was 32.4% compared to 34.7% for the same period last year.

At June 30, 2016, the company had a Tier 1 leverage ratio of 8.99%, down from 9.56% at June 30, 2015.

Asset Quality

The provision for loan losses for the 2016 second quarter was $0.1 million versus no provision for the same period last year. Nonperforming assets at June 30, 2016 were $10.6 million, compared to $10.1 million at June 30, 2015. Net charge-offs for the 2016 second quarter were $0.1 million, or 0.07% of average loans, annualized, compared to $0.1 million, or 0.08% of average loans, annualized for the same 2015 period. Year-to-date net charge-offs were $0.2 million, or 0.08% of average loans, annualized compared to $0.6 million, or 0.25% of average loans, annualized for the same period last year. The allowance for loan losses at June 30, 2016 stood at $6.4 million, or 1.10% of total loans, compared to $6.3 million or 1.29% of total loans at June 30, 2015.

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

Asset Quality History

(dollars in thousands)

Middlefield Banc Corp., headquartered in Middlefield, Ohio, is a bank holding company with total assets of $760.1 million at June 30, 2016. 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.bank.

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

June 30, 2016 and 2015

(Dollar amounts in thousands)

(unaudited)

MIDDLEFIELD BANC CORP.

Consolidated Selected Financial Highlights

June 30, 2016 and 2015 and December 31, 2015