A developing roller has a roller core, an electrically conductive layer provided on a circumferential surface of the roller core, and a covering layer provided on the outer circumferential surface of the conductive layer. The covering layer is formed by subjecting a reaction mixture containing a fluorine-containing polyol, a reactive silicone oil having an active hydrogen, and an isocyanate compound, to a reaction condition for reacting the fluorine-containing polyol and the reactive silicone oil with the isocyanate compound.