Mignoni has played in three of Toulon's four Heineken Cup matches this season, guiding the tournament newcomers to top of Pool 3.
In total, he has featured in 23 Heineken Cup matches, starting 22 of those games since his first tournament appearance for Beziers back in the 2002/03 season.
Mignoni also played three seasons of Heineken Cup rugby for Clermont Auvergne during his six years with the current French Champions.
He tasted Challenge Cup success with Clermont in 2007 and has featured in a total of 45 matches in the continent's second-tier competition.
Now in his third spell with Toulon, Mignoni has also played European rugby for Dax.
A winner of 28 international caps for France, Mignoni played in two World Cups and played a key role in his country's 2002 Grand Slam triumph.
Mignoni was officially added to the Toulon coaching staff at the beginning of this season, although it is as yet unclear whether he will move into coaching on a full-time basis following his retirement.
"Pierre Mignoni has not commented on the possibility of coaching next season. However, he has not ruled out this possibility," read a statement from last season's Amlin Challenge Cup Finalists.