It is an object of the present invention to improve workability when a filler is filled into inside of a roller body of a motorized roller. In order to achieve the above-mention object, the present invention provides a method for producing a motorized roller formed by accommodating a motor in a roller body so that the roller body is rotated when being driven by the motor, including the steps of a step of providing at least one elastic body, a step of providing a bag for accommodating the elastic body, a step of inserting the elastic body into the bag, a step of removing air from the bag, a step of inserting the bag accommodating the elastic body into a cavity of the roller body, and a step of taking air in the bag so as to expand the elastic body so that the cavity is filled with the bag accommodating the elastic body.