The 25-year-old has been with the club since 2007 and firmly established himself as a key man last season, with 18 goals in all competitions.
A statement on the club's official website read: "The club is happy to announce the prolongation of Cheick Diabate's contract. The Mali international is now linked to Les Girondins until 2016.
"It is good news for Les Girondins, who can now count on their centre-forward for several more years."
Diabate came through the club's youth system and had spells on loan with Ajaccio in 2008-09, scoring 14 goals in Ligue 2, and less productively with Nancy the following season.
The 6ft 4in frontman has scored 32 goals in 79 games for the club despite 36 of those appearances coming from the substitutes' bench. Last season's haul came in only 21 starts and he was the leading scorer in the Coupe de France, with six goals in four games.