Tsonga - seeded 13th - was too strong for Bulgarian seventh seed Dimitrov in the semi-finals, easing to a 6-4 6-3 win after an hour and 24 minutes in Toronto.
The Frenchman won three break points, saved all four presented to Dimitrov and won 88 per cent of his first service points as he reached his first ATP Tour final since finishing runner-up at the BNP Paribas Masters in 2011.
Tsonga - coincidently - lost that match-up to Roger Federer, who he will face in Sunday's decider after the Swiss second seed accounted for Spaniard Feliciano Lopez 6-3 6-4.
"I'm feeling good," said Tsonga.
"I have been waiting for this moment for a couple of years now.
"It's good because I have always believed in myself during all these years.
"It will for sure make me stronger and keep my motivation at the highest level."
A day after eliminating Andy Murray, Tsonga continued where he left off against Dimitrov, taking the opening set.
Tsonga, though, did not have it all his own way in the first stanza after being forced to save four break points as he attempted to serve for the set with a 5-4 lead.
The 29-year-old Frenchman ramped up the pressure in the second set, breaking twice as progressed to his third ATP World Tour Masters 1000 final.
Standing in Tsonga's way is Federer, who leads the head-to-head record 11-4.
Federer - Rogers Cup champion in 2004 and 2006 and runner-up in 2007 and 2010 - made light work of Lopez as he wrapped up proceedings in straight sets.
The 33-year-old sent down 13 aces and won 86 per cent of his first services points.
Federer also broke twice throughout the encounter, while he did not face a break point against Lopez.