To ensure high sensitivity, high durability and high potential by electrification, to suppress the reduction of sensitivity even after repeated use and to keep stable potential by electrification by using a specified azo compd.

A photosensitive layer contg. an azo compd. represented by the formula, etc., is formed on an electrically conductive substrate to obtain the objective electrophotographic photoreceptor. In the formula, each of R1 and R2 is H, halogen, alkyl which may have a substituent, etc., and Cp is a residue of a coupler. A photosensitive layer consisting of the azo compd., an electric charge transferring material and a film forming resin binder may be formed on the substrate. The photoreceptor may be a laminate type photoreceptor obtd. by forming an electric charge generating layer consisting of the azo compd. and a resin binder and an electric charge transferring layer consisting of an electric charge transferring material and a resin binder on an electrically conductive substrate. Any of the electric charge generating layer and the electric charge transferring layer may be formed as an upper layer. High sensitivity and high durability can be ensured.