Joel Parker (November 24, 1816 – January 2, 1888) was an American attorney and Democratic Party politician who served two non-consecutive terms as the 20th governor of New Jersey from 1863 to 1866 and 1872 to 1875. As a Democratic governor during the American Civil War, Parker was one of the leading critics of the Abraham Lincoln administration's domestic and military policy, though he was generally a supporter of the Union war effort.