A developing apparatus loadable with a developer container. The container having a developer of the desired color is selectively inserted into a developing apparatus and then rotated therein in a predetermined direction so that the developer container will be set in place within the developing apparatus. The developer container is detachable relative to the developing apparatus and includes a protrusion for positioning the developer container within the developing apparatus and another protrusion for discriminating the color of the developer in the selected container. The positioning protrusion is located upstream of the color discriminating protrusion in the above predetermined direction of rotation. The developing apparatus includes a developer receptacle including guide grooves for respectively guiding the positioning and discriminating protrusions of the developer container into the developer receptacle and a stopper surface which is engaged by the positioning protrusion of the developer container to limit the rotation thereof when the container is rotated within the developing apparatus in the predetermined direction.