The result eliminated the Asian team from the Championship while Canada is still in the running for the second place in Pool G.
Nicholas Hoag accounted for 29 of Canada points, John Gordon Perrin ended with 28.
Once again Amir Ghafour led Iran in scoring, finishing with 24 points.
The 2018 championship is the 19th staging of the FIVB Volleyball Men's World Championship, contested by the senior men's national teams of the members of the Fédération Internationale de Volleyball (FIVB), the sport's global governing body.
The final tournament is being held in Italy and Bulgaria from September 9 to 30. For the first time the tournament is jointly-hosted by more than one country.
The final six will be hosted by Italy at the Pala Alpitour in Turin.