The boy's father was driving the snowmobile on a rural road when it struck another vehicle.
"It's a region where there is a horse crossing, and the snowmobile wanted to cross. That's when there was a collision with a vehicle," said Quebec police spokeswoman Sgt. Catherine Viel.
The driver was injured but authorities say he should survive.
The driver of the vehicle was treated for shock.
Police say alcohol and speed were not factors in the crash.
"It's a windy region. It was snowing. It's possible that visibility was reduced for drivers," said Sgt. Viel.
This is the 17th snowmobile-related death in the province this year.
Last year, 19 people died while riding snowmobiles.