Officers seized over C$3.5 million ($2.53 million) worth of counterfeit merchandise from a Mississauga warehouse, they said, including more than 16,000 fraudulent jerseys and flags bearing fake FIFA, Nike, Adidas, and Puma branding, as well as two counterfeit World Cup trophies.
Two men have been arrested and charged, the police said.
Toronto is expecting more than 300,000 visitors during the World Cup, with six matches to be played in the city, including Canada's opener against Bosnia and Herzegovina on June 12.
A complaint to the Toronto Police Service FIFA Planning Team Investigative Unit in May alleged that the accused were supplying products to retail stores and acting as a distributor of fraudulent merchandise.
The items have an estimated street value of C$3,564,000, police said.
($1 = 1.3831 Canadian dollars)