There is provided a roller including: a roller body part; and a rubber part attached to the roller body part, the rubber part including: a rubber body part provided on an outer circumference of the roller body part; and a side extending part extending on a side face of the roller body part from a side face of the rubber body part, wherein the roller body part has a recess portion formed on the side face of the roller body part, and into which the side extending part is fitted.