The present invention can transfer a belt member on a supply conveyor onto a building drum from an inclined distal end portion while holding on both side edge portions in the width direction thereof and can efficiently adhere the belt member according to the rotation of the building drum. As a means for such building, using a supply conveyor (5) which places the belt member (B1) thereon and a hand device (10) which includes holding members (17a), (17b) having press plates (16a), (16b) extending in the feeding direction of the supply conveyor. In a state that a distal end portion of the belt member (B1) on the supply conveyor is held on a lower surface of the press plates (16a), (16b) of the hand device (10), the belt member (B1) is transferred to the building drum (D) along with a feeding operation of the supply conveyor (5) and, at the same time, the belt member (B1) is adhered by pressing to a peripheral surface of the building drum (D) from a distal end portion thereof while rotating the building drum along with the transfer of the belt member.