An image forming apparatus including a cartridge including an image carrying member and a positioning portion, and an apparatus main body. The apparatus main body including an opening portion, a rotatable opening and closing member, the opening and closing member including an engaging portion and being rotatable between a first position and a second position, an engaged portion, an abutment portion that determines a position of the attached cartridge, and a pressing portion applying pressing force to the cartridge. The opening and closing member rotates from the first position to the second position against counterforce of the pressing force, and the engaging portion is provided in an area of the opening and closing member that is closer to the rotational axis than an area of the opening and closing member that receives the counterforce.