Ligny-en-Barrois is a commune in the Meuse department in Grand Est in north-eastern France. The town is in the arrondissement of Bar-le-Duc, beside the canal that links the rivers Rhine and Marne, fifteen kilometres to the south east of Bar-le-Duc: it is the administrative seat of the canton of Ligny-en-Barrois. The area of Ligny-en-Barrois is 32.26 km2. A principal employer is the French Evobus motor bus assembly plant.