A developing cartridge is detachably mountable to a main assembly of an image forming apparatus, and includes a frame, a developer carrying member, a first portion to be engaged provided on one side of the frame, and a second portion to be engaged provided on the other side of the frame with respect to the direction crossing the axial direction of the developer carrying member. In addition, a cover member includes a first engaging portion engageable with the first portion to be engaged and a second engaging portion engageable with the second portion to be engaged for covering an exposed portion of the developer carrying member by being detachably mounted to the frame. The cover member is detachably mountable to the frame in a first state by engaging the first engaging portion with the first portion to be engaged and by engaging the second engaging portion with the second portion to be engaged.