Toronto police Sgt. Doodnath Churkoo says that the car was left running while the boy's father went into the restaurant to pick up some food.
The child's mother was in the rear seat of the vehicle, while the boy was left in the driver's seat.
Churkoo says the boy put the car in gear, causing the vehicle to drive into the McDonald's, which is located in the Jane Street and Finch Avenue area in the northwest section of the city.
When police arrived at the scene, the mother claimed she was driving when the car hit the fast-food restaurant. But Churkoo says witnesses told police that the child was in the driver's seat when the accident happened.
Churkoo says both parents have been charged with obstructing a peace officer.