Colfontaine (; ; ) is a municipality of Wallonia located in the province of Hainaut, Belgium.
On 1 January 2006, the municipality had 20,021 inhabitants. The total area is 13.62 km<sup>2</sup>, giving a population density of 1,470 inhabitants per km<sup>2</sup>.
The municipality consists of the following districts: Pâturages, Warquignies, Wasmes (town centre; it includes the village of Petit Wasmes).