Hajj Muhammad Legenhausen (born May 3, 1953) is an American philosopher and professor of philosophy at the Imam Khomeini's Educational and Research Institute.

He has been an advocate of interfaith dialogue, and serves on the advisory board of the Society for Religious Studies in Qom.

Since 1996, he has been studying Islam and teaching Western philosophy and Christianity at the Imam Khomeini Education and Research Institute in Iran.

Brought up as a Catholic, he abandoned religion shortly after beginning his academic studies at the State University of New York at Albany.

In 1979, he became acquainted with Islam through Muslim students at Texas Southern University, where he taught from 1979 to 1989.