The cars didn't completely disappear — the nose of one of the cars slipped into the hole while the side of the other car was partially submerged.
A spokesman for Montreal's airport authority says the hole is just under a metre deep and covers an area of about five metres long and three metres wide.
Francois Asselin says it's located in an outdoor employee parking lot and stressed it won't disrupt business at the airport.
No one has been injured and the cars were pulled out by mid-afternoon.
Police and firefighters have cordoned off the area in case the hole widens.
Also on HuffPost