Chertsey is a municipality in the regional county municipality (MRC) of Matawinie in Quebec (Canada) located in the administrative region of Lanaudière.
Chertsey is located in the first mountains of the Laurentians less than an hour from Montreal. Formerly partly cleared and cultivated, the territory has returned to the original forest. There are many beautiful lakes there; the territory is crossed by the Ouareau river which drains the Jean-Venne and Burton rivers. The Ouareau forest park occupies the north of the township.