The new deal will keep Mangane at Rennes until the summer of 2014.
Mangane has recently been linked with the likes of Sunderland, Marseille and Lyon.
The 28-year-old said: “I am delighted to stay with Rennes until 2014.
“I thought about things for a long time and I think I have made the right decision. Rennes are a fantastic club.
“They are not Lyon, with all the glamour and the big business, but they are the ideal club for me.
“I am 28 now, I have reached my peak and I need to prove again this season that I can maintain those standards.”