Valleyfield, officially Salaberry-de-Valleyfield, city in Beauharnois County, southern Québec province, Canada. The city is located on Lac-St-François (Lake Saint Francis), a widening of the St. Lawrence River, near Montréal. It is a port and a commercial and manufacturing center situated on a group of small islands. Major products include textiles, clothing, chemicals, refined metals, paper, and wood items. It was incorporated as a city in 1904. Population (1996) 26,600.
