Amir Qalenoi's men won the decisive victory at Shahid Rajaei Stadium in the city of Qazvin on Friday afternoon.
Emad Reza (7'), Ebrahim Toreh (11'), Ehsan Hajisafi (48') and Ahmad Jamshidian (56') scored for Sepahan, while Meisam Rezapour netted the only goal for Peykan, coached by Hamid Derakhshan.
Sepahan, which retains its top standing with 31 points, is followed by Esteqlal and Zob Ahan which will play Rah Ahan and Foulad on Saturday respectively.
The 18 teams participating in the Iranian Premier League will then rest until November 27.
Friday match results
Sepahan 4-1 Peykan
Pas 3-1 Saipa
Malavan 1-0 Saba
Teraktorsazi 3-2 Esteqlal Ahvaz