A charging device including a charging roller having a metallic cylinder with an elastic layer disposed thereon, and a cleaner for cleaning the surface of the charging roller. The cleaner includes a driving shaft and a cleaning roller rotatably mounted on the driving shaft. The cleaning roller is made of a non-cellular foam resin having a density of from 5 to 15 kg/m.sup.3 and a tensile strength of from 1.2 to 2.2 kg/cm.sup.2.