A developer amount regulation blade structure that effectively reduces assembly cost and improves image quality configured to form a layer of a developer on a developer bearer includes a regulation blade configured to regulate a thickness of the developer on the developer bearer, a first supporting member configured to support the regulation blade maintaining a gap between the regulation blade and the developer bearer, and a second supporting member configured to sandwich the regulation blade tightly with the first supporting member, wherein at least one of the first supporting member and the second supporting member is made of a plastically deformable material, and the second supporting member and the first supporting member sandwich the regulation blade by at least two plastically deformed portions separated from each other in a longitudinal direction of the first supporting member and connecting the first supporting member and the second supporting member.