Provided is an image forming apparatus, having: a power source; a first coupling member configured to be rotated by a driving force transferred from the power source; and a cartridge including a second coupling member configured to rotate in a state of being adsorbed to the first coupling member, and a rotating member connected with the second coupling member, wherein the first coupling member has a first driving force transfer surface which is perpendicular to a rotation axis of the first coupling member, the second coupling member has a second driving force transfer surface which is perpendicular to a rotation axis of the second coupling member, and the driving force is transferred from the first coupling member to the second coupling member in a state where an adsorption force is generated mutually between the first driving force transfer surface and the second driving force transfer surface.