An electrophotographic photoreceptor includes a conductive substrate, a charge generation layer on the conductive substrate, a charge transport layer on the charge generation layer, and a protection layer on the charge transport layer, in which a ratio L/ of a total thickness L (m) of the charge transport layer and the protection layer to a dielectric constant (F/m) of the charge transport layer and the protection layer as a whole in a thickness direction is 3 or more and 6 or less.