The Bad Heart River is a short river in northern Alberta, Canada. It is a tributary of the Smoky River.
Bad Heart River's name is an accurate preservation of its native Cree-language name, maatsiti.
It originates in Saddle Hills County of the Peace River Country, north of Sexsmith and south of Rycroft, at an elevation of . After descending the slopes of the Saddle Hills, it is crossed by Highway 2, then flows north-eastward. After being crossed by Highway 733, it continues eastward, receives the waters of Kakut Creek, then flows through a deep canyon and empties into the Smoky River at an elevation of .