An image forming method that includes the steps of providing a developer comprising at least colored resin particles, a fluidity improver having a specific chargeability and magnetic particles wherein the colored resin particles have a volume-average particle size of 4-10 microns and a specific volume-basis particle size distribution; supplying the developer to a surface of a developer-carrying member disposed opposite to a latent image-bearing member having thereon an electrostatic latent image; carrying the developer on the surface of the developer-carrying member; and developing the electrostatic latent image on the latent image-bearing member with the developer in a developing zone where the latent image-bearing member is disposed opposite to the developer-carrying member to form a toner image; wherein an alternating electric field comprising an AC component and a DC component is imparted to the developing zone under specific conditions.