A developing roller for an electrographic imaging apparatus, which
comprises a base rubber, a conductive carbon black, a conductive polymer
for controlling hardness of the base rubber and dispersion of the carbon
black, and a binder resin for inhibiting migration of the conductive
polymer to a surface of the developing roller, and an electrographic
apparatus comprising the same are provided. The developing roller has
excellent hardness, processibility, stability to resistance and
resistance to migration.