The six-time IndyCar champion passed polesitter Colton Herta for the lead when the Andretti Autosport driver was still bringing his tyres up to temperature having pitting one lap later than Dixon, and held on to win by 0.8 seconds after 85 laps of the Canadian street track.
His 52nd career victory meant the Chip Ganassi Racing driver drew level with Mario Andretti in the all-time win stakes, albeit 15 behind record-holder AJ Foyt.
It also extended his run of IndyCar seasons with at least one win to 20 and marks the 18th consecutive season in which he has won a race, having last gone winless in Ganassi's tough 2004 season with Toyota engines.
Dixon, whose last win had come at Texas in the third round of the 2021 season, moves up to fifth in the standings, just 44 behind team-mate and points leader Marcus Ericsson.
Speaking about equalling the win record of four-time champion Andretti, Dixon said: "It's amazing to be close to Mario.
“I'm just so thankful that he and AJ [Foyt] are in the pits and we get to talk to them. It's huge, it feels so good to be a part of this group.”
Mario Andretti hit Twitter to say: “Utmost respect for my friend @scottdixon9 and truly happy to congratulate him on 52 wins.
“Also congratulate his team because nobody does it alone. I hope this is just a step on your continuing journey. Well done.”
Dixon, who had CGR technical director Chris Simmons back on race engineer duties with his #9 car for the first time since 2019 while usual race engineer Michael Cannon was working on a secret project at Ganassi's Indianapolis race shop, revealed after the race that he had struggled with rear tyre degradation after making some adjustments after the warm-up.
Speaking to Peacock, Dixon said: “It was a tough drive. Ended a streak there, which is just fantastic.
“It's been a funny year for the #9 and I still feel bad for what happened in the 500 [when he was hit with a pitlane speeding penalty while in contention to win].
“Being back in Winners' Circle feels good, and massive thanks to Honda, because getting that fuel mileage today was so easy.”
Asked about his recent comment regarding the need to get on a roll in order to claim the title and match Foyt for the IndyCar record of seven championships, Dixon said: "I'm hoping this is the start of the roll. The team has been working as hard as any.”
