An electrophotographic photoreceptor includes a cylindrical conductive substrate, an undercoat layer containing a cured product of a resin and a blocked isocyanate and being disposed on the conductive substrate, and a photosensitive layer on the undercoat layer. The degree of curing of the undercoat layer defined by the equation below is about 1.5 or less in both a region A and a region B defined below: Region A (B): A region between a position distant from a first (second) end of the conductive substrate by about ⅛ of a length of the conductive substrate and a position distant from the first (second) end of the conductive substrate by about ⅕ of the length of the conductive substrate Degree of curing=[Amount (g) of blocking agent separated from blocked isocyanate in undercoat layer]/weight of undercoat layer (g)×100.
