A developing roller is provided, which includes a roller body having a simplified structure without a coating film and yet having a higher wear resistance. The developing roller (1) includes a roller body (2) made of a crosslinked product of a rubber composition containing a rubber component including 20 to 50 parts by mass of ECO and/or GECO as an ion conductive rubber and 50 to 80 parts by mass of NBIR based on 100 parts by mass of the overall rubber component, and an oxide film (6) formed in an outer peripheral surface (5) of the roller body (2) by irradiation with ultraviolet radiation or the like.