An electrophotographic image forming apparatus includes a cartridge supporting member movable between an inside position in the main assembly of the apparatus and an outside position outside the main assembly. The apparatus further includes a first opening through which the cartridge supporting member passes between the inside position and the outside position and a first openable member for openably closing the first opening. A second opening is provided continuing from the first opening and provided above the first opening, with the second opening being effective to permit the cartridge to be removed from the cartridge supporting member in the state that the cartridge supporting member takes the outside position and being effective to permit the supporting member to support the cartridge. The apparatus also includes a second openable member for openably closing the second opening.