George Grennell Jr. (25 December 1786-19 November 1877) was a member of the US House of Representatives (NR-MA 7) from 4 March 1829 to 3 March 1833 (succeeding Samuel Clesson Allen and preceding George N. Briggs) and from MA-6 from 4 March 1833 to 3 March 1839 (succeeding Joseph G. Kendall and preceding James C. Alvord). Born in Greenfield, he practiced law before serving as Franklin County prosecuting attorney from 1820 to 1828, in the state senate from 1825 t o1827, in Congress, and later as a judge.