An attaching device for an annular member , for attaching the annular member to an inner peripheral surface of a tire , the attaching device comprising: a plurality of holders disposed at intervals in a circumferential direction about a predetermined axis (C1) and configured to hold an inner peripheral surface of the annular member ; a moving mechanism configured to move the plurality of holders in a radial direction about the axis (C1); a rotating mechanism configured to move the plurality of holders in the circumferential direction; and a control device , characterized in that the control device controls operation of the holders , the moving mechanism , and the rotating mechanism so as to perform the following operations (a) to (f) of: (a) holding the inner peripheral surface of the annular member by the holders ; (b) moving the holders holding the annular member , outwardly in the radial direction toward a predetermined attaching position to attach a part of the annular member to the inner peripheral surface of the tire ; (c) releasing the holding of the annular member by the holders ; (d) moving the holders to a retraction position which is located inward of the attaching position in the radial direction, to separate the holders from the annular member ; (e) moving the holders in the circumferential direction; and (f) moving the holders to the attaching position to attach another part of the annular member to the inner peripheral surface of the tire . a plurality of holders disposed at intervals in a circumferential direction about a predetermined axis (C1) and configured to hold an inner peripheral surface of the annular member ; a moving mechanism configured to move the plurality of holders in a radial direction about the axis (C1); a rotating mechanism configured to move the plurality of holders in the circumferential direction; and a control device , characterized in that the control device controls operation of the holders , the moving mechanism , and the rotating mechanism so as to perform the following operations (a) to (f) of: (a) holding the inner peripheral surface of the annular member by the holders ; (b) moving the holders holding the annular member , outwardly in the radial direction toward a predetermined attaching position to attach a part of the annular member to the inner peripheral surface of the tire ; (c) releasing the holding of the annular member by the holders ; (d) moving the holders to a retraction position which is located inward of the attaching position in the radial direction, to separate the holders from the annular member ; (e) moving the holders in the circumferential direction; and (f) moving the holders to the attaching position to attach another part of the annular member to the inner peripheral surface of the tire . (a) holding the inner peripheral surface of the annular member by the holders ; (b) moving the holders holding the annular member , outwardly in the radial direction toward a predetermined attaching position to attach a part of the annular member to the inner peripheral surface of the tire ; (c) releasing the holding of the annular member by the holders ; (d) moving the holders to a retraction position which is located inward of the attaching position in the radial direction, to separate the holders from the annular member ; (e) moving the holders in the circumferential direction; and (f) moving the holders to the attaching position to attach another part of the annular member to the inner peripheral surface of the tire . <EOS>