The entry in Canada was the same as it had been a fortnight earlier in Monaco and Ayrton Senna was on pole in his McLaren-Honda, as he had been in Monaco. He was followed by his team mate Gerhard Berger, Alain Prost's Ferrari and the Benettons of Sandro Nannini and Nelson Piquet. The top 10 was completed by Thierry Boutsen (Williams), Nigel Mansell (Ferrari), Jean Alési (Tyrrell), Riccardo Patrese (Williams) and Stefano Modena (Brabham).

At the start the track was damp and Berger jumped the start. He then hesitated and so ended up with worst of both worlds, being in second place and getting a one minute penalty. Senna was ahead and Berger had Nannini and Alési behind him. The track quickly dried out and Berger was the first to stop for dry tyres. Senna followed and so Nannini was briefly in the lead before going into the pits himself. When he rejoined he hit a groundhog and had to return to the pits to have the remains of the dead animal removed from his sidepod. The pit stops left Berger ahead of Senna and the Austrian began to try to make up for his minute penalty. Alési had also dropped back, having removed his rear wing on the back of de Cesaris. This left Prost and Boutsen battling for third on the road with Piquet, Mansell, Warwick (Lotus), Patrese and Donnelly (Lotus) chasing. On lap 20 Boutsen overtook Prost but as he did so he hit some standing water and spun in front of Prost and took out backmarker Nicola Larini (Ligier). Nannini was charging back after hitting the groundhog but went off at the hairpin and parked his Benetton there. Five laps later Alési slid off and hit the Benetton, which ended up in several pieces.

While Senna continued to lead, the battle for second place continued with Piquet eventually winning the day and Prost dropping behind Mansell and then Berger. Prost finished fifth with Derek Warwick sixth in his Lotus.