A mechanism for mounting and removing a toner cartridge in a development device for use in an electrophotographic recording apparatus or a photocopier includes a rotating member for mounting a cartridge filled with toner for replenishing onto a main body at a set position and opening a toner opening. A cross-shaped projection on the main body and a cross-shaped groove on the cartridge are provided for preventing lifting of the cartridge when the rotating member is rotated in one direction. The rotating member is rotated from the set position in another opposite direction, and is subsequently returned to the set position to have the projection and the groove engaged or disengaged.