The Louvart River is a tributary of the south shore of the Lepallier River flowing into the municipality of Eeyou Istchee Baie-James (municipality), in the administrative region of Nord-du-Québec, in Quebec, in Canada.

The course of the Louvart River is located southwest of James Bay Reserve.

The surface of the Louvart River is usually frozen from early November to mid-May, however, safe ice circulation is generally from mid-November to mid-April.

This hydrographic slope has its source at Louvart Lake (length: 7.5 kilometres (4.7 mi); altitude: 214 metres (702 ft)).

The mouth of this lake is located at 6.3 kilometres (3.9 mi) north-east of the Nottaway River, at 14.6 kilometres (9.1 mi) west of Rodayer Lake (elevation): 250 metres (820 ft)) (which is the head lake of the Lepallier River) and at 63.1 kilometres (39.2 mi) west of Evans Lake.