Andover Theological Seminary (1807–1965) was a Congregationalist seminary founded in 1807 and originally located in Andover, Massachusetts on the campus of Phillips Academy.
From 1908 to 1931, it was located at Harvard University in Cambridge, Massachusetts. It then collocated with Newton Theological Institution (NTI) in Newton, Massachusetts. Then, in 1965, Andover Theological Seminary and NTI formally merged in 1965 to form Andover Newton Theological School in Andover, Massachusetts. In its original and merged forms, it is the first and thus the oldest Protestant theological seminary in the United States. The seminary continues as Andover Newton Seminary at Yale Divinity School, which was launched in 2017.