A contact-separation device brings a contact-separation member into contact with a contacted member separably and includes a biasing member that generates a biasing force. A presser presses the contact-separation member against the contacted member in a pressing direction with the biasing force from the biasing member. A cam presses the presser in an opposite direction being opposite to the pressing direction. The cam is rotatable and has a cam face. A cam follower has a cam contact face that contacts the cam face of the cam. The cam contact face is curved to project toward the cam. The cam contact face has a curvature that is smaller than a greatest curvature of the cam face of the cam and is greater than a smallest curvature of the cam face of the cam.