Taylor Paris scored two tries and Nathan Hirayama had four conversions for Canada, which beat Fiji for only the second time.
The win came after Canada defeated Tonga 28-5 and Spain 31-7 earlier in the day.
Against Fiji, Paris scored a try just 47 seconds into the game and added another at 6:18 with a convert from Hirayama to tie the game at 14.
Canada then went into halftime with a 21-14 lead after Paris found Sean Duke for another try and convert from Hirayama.
Ilai Tinai scored a try for Fiji 49 seconds into the second half, but the ensuing convert was missed. Then Canada's John Moonlight added another try and Hirayama hit his fourth convert of the match to finish off Fiji.