To provide a developing roller whose durability against the repeated deformation due to compressive stress and tensile stress applied to a toner carrying layer on the surface of the developing roller is enhanced by controlling the cross-linking degree of resin forming the toner carrying layer on the surface of the developing roller, and to provide a developing device that uses the developing roller.

The developing roller used for the developing apparatus comprises a conductive shaft body 2, an elastic semiconductor layer 3 positioned outside the conductive shaft body 2 and a toner-carrying layer 4 provided on the outer peripheral part of the elastic semiconductor layer 3, and prepared for visualizing an electrostatic latent image formed on a latent image carrier, after forming a toner layer of prescribed thickness with triboelectrification toner carried on the toner carrying layer 4 in a thin-film state by a layer forming member. The gel fraction of the resin which forms the toner carrying layer 4 is ≥60%, and it takes one minute or longer, until the toner carrying layer 4 is lost when the developing roller 1 is rotated at 100 rpm, while pressing a sandpaper having an average grain size of 30 μm against the surface of the toner carrying layer 4 with a pressure of 0.1 kgf.