To provide a stable good-quality developing roller without causing the surface staining of an OPC by optimally setting the composition of the surface structure of the developing roller and carrier so that the occurrence of reversely electrified toner which causes trouble of the surface staining of the OPC may be restrained.

In this two-component developing method using the toner electrified to be negative, the developing roller having resin incorporating nitrogen in resin structure and having the ratio of the content nitrogen that the number of the atoms of a carbon atom is ≤100 in the case of setting that the number of the atoms of a nitrogen atom is 1 on average at least on its surface is used.