An electrophotographic image forming method is disclosed. In the method electrostatic latent image is developed by a non-magnetic single-component developing system, in which a non-magnetic single-component developer is conveyed by a developer carrying member, the developer carrying member is contacted with a developer layer regulation member for regulating an amount of the developer at the surface of the developer carrying member, and a binder resin of the developer comprises a vinyl polymer having an acid value of from about 5 to about 30 mgKOH/g and a ratio of hydroxyl group value/acid values from about 0.3 to about 0.8.