Denain (French pronunciation: [dənɛ̃]; Picard: Dnain) is a commune in the Nord department in northern France.

It is the largest of 47 communes which comprise the Communauté d'agglomération de la Porte du Hainaut, which in 2017 had a total population of 158,754.

[4] Its vicinity was the scene of the decisive victory gained in 1712 by Marshal Villars over the allies commanded by Prince Eugene of Savoy; and the battlefield is marked by a monolithic monument inscribed with the verses of Voltaire: "Regardez dans Denain l'audacieux Villars/Disputant le tonnerre à l'aigle des Césars.

Former mayor Patrick Roy was also a deputy and became famous for the support for heavy metal music he expressed at the National Assembly on various occasions.

(Artres, Bettrechies, Cerfontaine, Denain, Eth, Lesquin, Obies, Quérénaing, Semousies, Wambrechies and Warlaing use the same arms.)