| William Parmenter | |
| State1: | Massachusetts |
| Term Start1: | March 4, 1837 |
| Term End1: | March 3, 1845 |
| Predecessor1: | Samuel Hoar |
| Successor1: | Benjamin Thompson |
| Office2: | Member of the Massachusetts Senate |
| Term2: | 1836 |
| Office3: | Member of the Massachusetts House of Representatives |
| Term3: | 1829 |
| Birth Date: | 30 March 1789 |
| Birth Place: | Boston, Massachusetts |
| Death Place: | East Cambridge, Cambridge, Massachusetts |
| Party: | Democratic |
| Occupation: | Banker Businessman |
William Parmenter (March 30, 1789 - February 25, 1866) was a United States representative from Massachusetts. He was born in Boston on March 30, 1789. He attended the city's public schools, including the Boston Latin School.
He was a member of the Massachusetts House of Representatives in 1829, served in the Massachusetts State Senate in 1836 and was a Cambridge selectman in 1836. He was manager and agent of the New England Crown Glass Co., and president of the Middlesex Bank. Parmenter was elected as a Democrat to the Twenty-fifth and to the three succeeding Congresses (March 4, 1837 – March 3, 1845), serving as chairman of the Committee on Naval Affairs in the Twenty-eighth Congress. He also served as a naval officer at the port of Boston 1845–1849.
He died in East Cambridge, Massachusetts on February 25, 1866. His interment was in Cambridge Cemetery.