An image forming apparatus can include a body casing and a photosensitive member unit configured to be inserted into and withdrawn from the body casing. The photosensitive member unit can be moved between a first position where the photosensitive member unit is stored in the body casing and a second position where the photosensitive member unit is withdrawn from the body casing, and between the second position and a third position where the photosensitive member unit is withdrawn from the body casing. The image forming apparatus may further include a control member disposed in the body casing, The control member can be configured to move between a holding position in which the photosensitive member unit is prevented from moving between the second position and the third position and a release position where the photosensitive member unit is allowed to move between the second position and the third position.