Port-Cartier is a city in the Côte-Nord region of Quebec, Canada. It is located on the north shore of the St. Lawrence River at the mouth of the Aux-Rochers River, 63 kilometres southwest of Sept-Îles, Quebec. Port-Cartier had a population of 6,516 at the 2021 Canadian census. It has a land area of 1,092 square kilometres, ranking 27th in area among all Canadian cities and towns.