Iranian cleric and a Friday prayer imam in Kazerun, Mohammad Khorsand was stabbed to death in the south of the country, an Iranian news agency reported.
Khorsand was chosen by Ali Khamenei, Iran's supreme leader, to be his representative in Kazerun.
The Iranian police have identified a suspect of the attack, the agency said.
According to the agency, Khorsand was killed while returning to his home from a religious ceremony.
A cleric was also killed in April in the western city of Hamadan.