John Mordaunt, 2nd Baron Mordaunt (1508–1571) was an English baron and member of the House of Lords. He had previously represented Bedfordshire in the House of Commons of England. He was the eldest son of John Mordaunt, 1st Baron Mordaunt of Turvey by Elizabeth, the daughter and coheiress of Sir Henry Vere of Great Addington, Northamptonshire. He was knighted in 1533 and inherited the title Baron Mordaunt on his father's death in 1562.