Seneffe (French pronunciation: [sənɛf] ⓘ; Walloon: Sinefe) is a municipality of Wallonia located in the province of Hainaut, Belgium.

The Château de Seneffe, now a museum belonging to the French Community of Belgium, is located in the municipality.

Between 1965 and 1982 Seneffe was the location of a car plant belonging to British Leyland, which in its later years assembled models including the Mini and the Austin Allegro from crated kits shipped from the company's Cowley facility.

[3] The Seneffe plant was closed in 1982 as the company's aging model range lost market share across Europe, with further loss of demand resulting from the depressed state of the UK economy at the time.

With alternative employment opportunities limited, the plant closure triggered considerable bitterness locally.