Bernissart (French pronunciation: [bɛʁnisaʁ]; Picard: Bernissåt) is a municipality of Wallonia located in the province of Hainaut, Belgium.

On January 1, 2024, Bernissart had a total population of 11,878. The total area is 43.81 km², which gives a population density of 271 inhabitants per km².

The municipality consists of the following districts: Blaton, Bernissart, Harchies, Pommerœul, and Ville-Pommerœul.

A well-known tourist municipality renowned for its numerous natural sites, Bernissart has an altitude ranging from 15 meters in the Harchies Marshes (a notable natural area) to 81 meters in the Stambruges Forest.

Located in a border area, it shares its western boundary with Condé-sur-l'Escaut, France. A part of Bernissart even extends onto French territory, forming a hamlet attached to this French municipality.

Bernissart is crossed by three main historical canals: Blaton-Ath in the north, Nimy-Blaton-Péronnes, and Pommerœul-Antoing in the center, which converge at an intersection in Blaton, earning it the nickname "Little Venice of Hainaut". It is also traversed by the Pommerœul-Condé canal and, to the southeast near the E19 highway, by the Haine River.

The municipality is well-served by the N50 road, the E42 and E19 highways, as well as railway line 78, which serves the three stations within its territory.

Thanks to this strategic location, Bernissart is just 22 km from Mons and 24 km from Tournai, at the crossroads of major road, rail, and waterway networks.