William Foster, D.D. (3 July 1744 – November 1797) was a Church of Ireland bishop. The younger son of Anthony Foster, Chief Baron of the Irish Exchequer, and his first wife Elizabeth Burgh, he was chaplain to the Irish House of Commons (1780–89), then successively Bishop of Cork and Ross (1789–1790), Bishop of Kilmore (1790–1796) and Bishop of Clogher (1796–1797).