John Henry Martindale (March 20, 1815 – December 13, 1881) was an American lawyer, Union Army general, and politician.

He entered the United States Military Academy at West Point in 1831, and graduated in 1835.

He was appointed a brevet second lieutenant, but resigned from the Army the next year and began to study law.

After the retreat from Malvern Hill, he was brevetted a major general of volunteers, and appointed Military Governor of Washington, D.C., a post he held from November 1862 to May 1864.

John H. Martindale was New York State Attorney General from 1866 to 1867, elected in 1865 on the Republican ticket.