A developing device includes a rotatable developer carrying member enclosing a magnetic field generating portion including a plurality of magnetic poles and configured to carry a developer; and a resinous regulating portion provided at a position opposing the developer carrying member and configured to regulate an amount of the developer carried by the developer carrying member. The regulating portion is formed of a resin material containing magnetic powder, and at least a free end portion, opposed to the developer carrying member, of the regulating portion has relative permeability of 10 or more and 60 or less.