The new deal will keep the 25-year-old at the Ligue 1 side until the summer of 2014.
“I am very happy and proud. Committing to the ASSE has always been my first wish because I feel good here,” Perrin was quoted as saying on the club’s official website.
“There is something in Saint-Etienne that does not exist in other clubs. Negotiations have taken some time but today I am happy to continue the adventure.”
St Etienne coach Christophe Galtier said: “We often talked together about his future. Loic had made a wise decision to wait. Today, he made a very good decision to extend the adventure with us.
“I’m pleased for the club and for me as coach. Loic is an example for all. It’s real plus for our club. He has love for the jersey and respect for the institution. He truly embodies the ASSE.”
