In an electrophotographic photosensitive member comprising a conductive support, and provided thereon a charge generation layer, a charge transport layer and a protective layer in this order, the layer thickness a0 (&mgr;m) of the charge transport layer at the middle portion of the conductive support in its generatrix direction, the layer thickness b0 (&mgr;m) of the protective layer at the middle portion of the conductive support in its generatrix direction, the layer thickness a (&mgr;m) of the charge transport layer at a portion other than the middle portion and the layer thickness b (&mgr;m) of the protective layer at the portion other than the middle portion satisfy the following expression (1) in a region satisfying 0.8 (&mgr;m)≦(a0−a)≦3.0 (&mgr;m): b0×(a/a0)3≦b(&mgr;m)≦b0×(a/a0)1/4  (1). Also disclosed are a process cartridge and an electrophotographic apparatus which have such an electrophotographic photosensitive member.