Nzonzi joined the Isfahan based football club after a successful medical examination, Tehran Times reported.
He represented the French national football team 20 times from 2017 to 2020.
The 35-year-old midfielder played for Turkish side Konyaspor last season.
Jose Morais’s Sepahan started the 2024/25 Iran’s Persian Gulf Professional League (PGPL) with a 3-1 win over Chadormalu in Matchweek 1.
Nzonzi is Sepahan’s sixth signing in the summer.
MNA