John Millen (1804 – October 15, 1843) was a United States Representative and lawyer from Georgia.
Born in Savannah, Georgia, in 1804, Millen studied law, gained admittance to the state bar and practiced law in Savannah. Millen served in the Georgia House of Representatives in 1828, 1834, 1835, 1839, and 1840.
Millen was elected as a Democratic Representative from Georgia to the 28th United States Congress and died only several months after assuming office, serving in total from March 4, 1843, until his death in Savannah on October 15, 1843. He was buried in that city's Laurel Grove Cemetery.