An electrophotographic photosensitive member is formed of a support, and a photosensitive layer disposed on the support. The photosensitive layer is characterized by containing an azo pigment having an organic group represented by formula (1) below: ##STR1## wherein X.sub.1, Z.sub.1, k.sub.1, B, A, R.sub.1 and R.sub.2 are defined in the text. The group of the formula (1) may provide at least one of up to 4 azo-substituents of the azo pigment having an entire structure represented byAr.paren open-st.N.dbd.N--Cp) 1-4,wherein Ar denotes an aromatic or heterocyclic core unit, Cp denotes a coupler residue group, and --(N.dbd.N--Cp) denotes such an azo-substituent. The photosensitive member can exhibit good electro-photographic performances including high and stable sensitivity on repetitive use.