To provide an image forming method that is free from dark-and-light stripe images which result from multiple-reflection within a photoreceptor which is caused by coherent radiation and to provide an image forming device that forms a high quality image by the use of the method.

In the image forming method for forming an electrostatic image by scanning the surface of the photoreceptor having a photoreceptive layer on its conductive substrate with writing light having a wavelength λ (μm) and a spot diameter (μm), the maximum height in which a reference length which is substantially the same as the spot diameter of the writing light is taken away from a crosssectional curve of the photoreceptor surface along the main scanning direction is λ/(2n) or greater (n represents the refraction index of the photoreceptive layer at the wavelength λ (μm) of the writing light).