Trazegnies () is a town of Wallonia and a district of the municipality of Courcelles, located in the province of Hainaut, Belgium.
Having merged with the municipality in 1976, it is located halfway between Charleroi and La Louvière. A former mining area, it is the location of Trazegnies Castle.
Trazegnies gives its name to the Marquess of Trazegnies d'Ittre.