An image forming apparatus comprising a drawer unit; the drawer unit comprising a drawer member allowed to shift toward a storage unit in an inserting direction, or shift from the storage unit in a drawing direction, the drawer unit comprising: a lock member rotatably supported by the drawer member; a first regulation member that is included in the storage unit and engages with the lock member to regulate a shift of the drawer member in the drawing direction when the drawer member is located at a first position; a second regulation member that is included in the storage unit and engages with the lock member to regulate a shift of the drawer member in the drawing direction when the drawer member is located at a second position drawn from the first position; and an operation unit that rotates the lock member, wherein the first position is a position at which the drawer member is inserted to an innermost position of the storage unit, and the second position is a position at which the drawer member is drawn to a maximum in a state supported by the storage unit; wherein the operation unit receives a first operation in the drawing direction and a second operation in the inserting direction, and the lock member is released from engagement with the first regulation member by the first operation and released from engagement with the second regulation member by the second operation: characterized in that the lock member is allowed to engage with the first regulation member in a first posture of the lock member, is allowed to engage with the second regulation member in a second posture of the lock member rotated in a predetermined direction from the first posture, and is released from engagement with the second regulation member in a third posture of the lock member further rotated in the predetermined direction from the second posture, and the lock member is rotated to the second posture by the first operation, and rotated to the third posture by the second operation. a lock member rotatably supported by the drawer member; a first regulation member that is included in the storage unit and engages with the lock member to regulate a shift of the drawer member in the drawing direction when the drawer member is located at a first position; a second regulation member that is included in the storage unit and engages with the lock member to regulate a shift of the drawer member in the drawing direction when the drawer member is located at a second position drawn from the first position; and an operation unit that rotates the lock member, wherein the first position is a position at which the drawer member is inserted to an innermost position of the storage unit, and the second position is a position at which the drawer member is drawn to a maximum in a state supported by the storage unit; wherein the operation unit receives a first operation in the drawing direction and a second operation in the inserting direction, and the lock member is released from engagement with the first regulation member by the first operation and released from engagement with the second regulation member by the second operation: characterized in that the lock member is allowed to engage with the first regulation member in a first posture of the lock member, is allowed to engage with the second regulation member in a second posture of the lock member rotated in a predetermined direction from the first posture, and is released from engagement with the second regulation member in a third posture of the lock member further rotated in the predetermined direction from the second posture, and the lock member is rotated to the second posture by the first operation, and rotated to the third posture by the second operation.