In the case that a developer supply container is provided with a feeding portion for feeding a developer by receiving a rotational force and a pump portion for discharging the developer by reciprocation, and the rotational force and a reciprocating force are received from a main assembly side of an image forming apparatus, there is a liability that a driving connection is not properly established between a portion of the developer supply container for receiving the reciprocating force and a portion of the main assembly side for applying the reciprocating force.The developer supply container is provided with a drive converting mechanism for converting the rotational force received from the main assembly side to a force for operating a volume changing type pump.