Francis Jacob Harper (March 5, 1800 – March 18, 1837) was an American politician from Pennsylvania who served as a Democratic member of the Pennsylvania House of Representatives from 1832 to 1833, the Pennsylvania State Senate for the 2nd district from 1834 to 1836 and as representative-elect to the U.S. House of Representatives for Pennsylvania's 3rd congressional district. He died before Congress was called to session.