Image forming apparatus having a rotary body that includes shaft portions fitted into positioning grooves

An image forming apparatus includes: a rotary body; a rotary body retaining member; pressure members that press the rotary body retaining member along a direction to bring shaft portions of the rotary body into positioning grooves; and an operation member. When an open/shut cover is in an open position, the operation member comes into contact with the rotary body retaining member so as to press the rotary body retaining member in a direction to bring the shaft portions of the rotary body out of the positioning grooves. When the open/shut cover is swung to a close position, the operation member is contacted by the rotary body retaining member pressed by the pressure members, thereby bringing the operation member into contact with part of the apparatus body and keeping the operation member still. The rotary body retaining member and the operation member touch each other through elastic buffering members.