The present invention provides an electrophotographic photoreceptor, a process cartridge and an image forming apparatus including the same, wherein the electrophotographic photoreceptor prevents the generation of excessive residual potential, which usually occurs on a photoreceptor having a protective layer composed of an inorganic material, and achieves both of high durability and favorable electrical characteristics.An electrophotographic photoreceptor composed of a conductive substrate having thereon a photosensitive layer and a surface layer formed in this order, wherein the total composition ratio of a group 13 element, oxygen, and hydrogen to the total element content in the surface layer is 0.95 or more, and the abundance ratio of the oxygen to the group 13 element is from 1.1 to 1.5.