Dolbeau-Mistassini is a town in northern Quebec, Canada, at the confluence of the Mistassibi River, Riviere aux Rats and the Mistassini River, on Lac Saint-Jean. Dolbeau-Mistassini is in the Maria-Chapdelaine Regional County Municipality and is the commercial hub of Lac-St-Jean with big stores and shopping centres. The city was formed in 1997 through the amalgamation of the cities of Dolbeau and Mistassini.