The endless belt member which is rotationally moved as being tensioned by a plurality of tension members and which bears a toner image includes at least a base layer, a surface layer arranged on the outer circumference of the base layer, and a rib restricting movement of the belt member in the width direction intersecting to a rotational direction of the belt member, and the surface layer is harder than that of the base layer and an edge of the surface layer in the width direction of the belt is arranged at the inner side in the width direction from the rib.