Tsonga had the enthusiastic Marseille crowd at his back as he battled past Jan-Leddard Struff of Germany 7-6 (7-4), 7-5 in Saturday's semifinals.
Struff was ahead 5-3 in the eighth game of the second set, but Tsonga scored a pair of breaks and went on to win the final four games
Tsonga, who has won the Marseille title twice in the past five years, will take on hard-serving Ernests Gulbis of Latvia on Sunday. Gulbis, the No. 3 seed, ousted top-seeded Richard Gasquet 6-3, 6-2 in a match where he served up 15 aces.