Joseph Barker (October 19, 1751 – July 5, 1815) was an American Congregationalist minister who represented Massachusetts's 7th congressional district in the United States House of Representatives from March 1805 to March 1809. Barker was elected as a Democratic-Republican to the Ninth and Tenth Congresses and served from March 4, 1805 to March 3, 1809. He was not a candidate for renomination in 1808, but four years later served as a member of the state's House of Representatives in 1812 and 1813.