The Mistaya River is a short river in western Alberta, Canada. It flows through Banff National Park in the Canadian Rockies, and a section of the Icefields Parkway was built along its course.
Mistaya River originates in Peyto Lake, a glacial lake of typical blue colour (due to rock flour). Mistaya flows north-west, receiving the waters of creeks such as Delta, Silverhorn, Cirque, Noyes, Chephren, Totem, Epaulette, Bison, Kaufmann and Sarbach. A series of elongated lakes are formed along the river: Mistaya Lake and Waterfowl Lakes.
Mistaya merges into the North Saskatchewan River at the Saskatchewan River Crossing.
From its headwaters of Peyto Creek, Mistaya River has a total length of 38 km.
The origin of the name is from the Cree language: () means 'grizzly bear'.