(1813–1891), the son, was born in Chester, Pennsylvania. At 10 he sailed with his father to the West Indies. He served in the Mexican navy and was taken prisoner by the Spanish following the capture of his ship during a period of conflict between Spain and its former colony. In 1829 Porter entered the U.S. Navy as a midshipman. He fought at Veracruz and Tabasco in the Mexican War. After the war, he commanded merchant ships until 1855, when he went back on active duty with the Navy.

During the Civil War, Porter played an important role in several major naval actions. He commanded a mortar flotilla (a fleet of mortar-equipped boats) under Farragut, his foster brother, in the capture of New Orleans, then took command of the Navy's Mississippi Squadron. Porter's ships provided naval support in 1863 in Union victories at Arkansas Post and Grand Gulf, and in the capture of Vicksburg, after which he was promoted to rear admiral. He led naval forces in the Red River Campaign in Texas in 1864 and then commanded the North Atlantic Blockading Squadron, which captured Fort Fisher in North Carolina in 1865.

Porter reorganized the U.S. Naval Academy as its superintendent, 1865–69. He became vice admiral in 1866 and admiral in 1870, the second man to hold that rank. (Farragut was the first.)