To provide an image forming apparatus for which very good thin line reproducibility, high image quality and high transferability are ensured even at low temperature and low humidity or high temperature and high humidity environment, and in which toner filming hardly occurs on the surface of a photoreceptor and the surface of an intermediate transfer member, and to provide an electrophotographic photoreceptor, an image forming unit and an image forming method.

In the image forming apparatus, a toner used in a developing device is a toner, having an average circularity of 0.920-0.995, and a mixed compound having a structure of Formula (1): X-(CTM group)n-Y and satisfying x+y≤99% is used as a charge transport material, wherein x represents the composition ratio of a compound of the largest component of the mixed compound having an n-based distribution; and y represents the composition ratio of a compound of the second component. In the Formula, CTM group is a charge transport group; X and Y each represents H, halogen or a monovalent organic group; and n denotes an integer of 0-10.