Abstract: A doctor blade mounting structure for mounting a doctor blade to a main body of a development device is provided, which includes a development roller which is rotatably arranged in the main body and on the outer circumferential surface of which a magnetic brush is formed. The doctor blade is disposed in confrontation with the development roller with a predetermined gap defined between the distal end of the doctor blade and the outer periphery of the development roller, for setting the height of the magnetic brush to a uniform level. The mounting structure is provided with a rigid support plate to which the doctor blade is attached, and fixing screws for fixing the rigid support plate to the main body of the development device are provided. The doctor blade is mounted to the main body of the development device through the support plate.