Ligny-en-Barrois (French pronunciation: [liɲi ɑ̃ baʁwa]) 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.

A principal employer is the French Evobus motor bus assembly plant.

Ligny is also the home town of the Essilor company which specialises in ophthalmic lens production.

[citation needed] The inhabitants are called Linéens in French.