Canada's main stock exchange dropped more than 8 percent to close at its lowest level in four years.
The Toronto Stock Exchange dropped 756.38 points, or 8.14 percent, to 8,537.34.
The exchange is heavily weighted with oil and commodity stocks.
Canada's major five banks also dropped more than 5 percent each.
Falling commodity prices and economic pessimism also sent the Canadian dollar down 0.97 cent to 77.59 U.S. cents, its lowest level in four years.