The Canton of Leforest is a former canton situated in the department of the Pas-de-Calais and in the Nord-Pas-de-Calais region of northern France. It was disbanded following the French canton reorganisation which came into effect in March 2015. It had a total of 23,699 inhabitants (2012).
The canton is organised around Leforest in the arrondissement of Lens. The altitude varies from 20 m (Courcelles-lès-Lens) to 66 m (Leforest) for an average altitude of 27 m.
The canton comprised 4 communes: