A developing apparatus includes a developing container for accommodating a developer including magnetic particles; a developer feeding member, provided in the developing container and having a magnetic shaft, for feeding the developer; a bearing rotatably supporting the shaft; a bearing accommodating portion; and a magnet, provided around the shaft at a position inside the bearing in the bearing accommodating portion, for forming a magnetic seal of magnetic particles by a magnetic field formed between itself and the shaft. The bearing accommodating portion includes a first space between the magnet and the bearing and a second space which is provided outside of the bearing with respect to a diametrical direction and which is in fluid communication with the first space to receive the developer from the first space.