Hasan Ali Mansur was an Iranian politician who served as Prime Minister from 1964 to 1965. He served during the White Revolution of the Shah Mohammad Reza Pahlavi and was assassinated by a member of the Fada'iyan-e Islam.

Fadayan-e Islam is a Shia fundamentalist group in Iran with a strong activist political and terrorist orientation. The group was founded in 1946, and registered as a political party in 1989. It was founded by a theology student, Navvab Safavi. Safavi sought to purify Islam in Iran by ridding it of 'corrupting individuals' by means of carefully planned assassinations of certain leading intellectual and political figures.