A charging roller for a contact charging assembly is provided including a conductive substrate, an elastic layer which covers the periphery of the conductive substrate, and a seamless tube externally so fitted as to cover the periphery of the elastic layer. The seamless tube constitutes a surface layer of the charging roller, and the charging roller has a surface of 3.0 .mu.m or less in ten-point average roughness (Rz jis 94) and 0.10 mm or less in roughness curve average length (RSm).