A sealing member fitting apparatus includes a sealing member transfer device that switches between a sealing member receiving position where the sealing member transfer device faces a sealing member holding device provided with a hollow sealing member and a sealing member fitting position where the sealing member transfer device faces an electrical wire clamping device. The sealing member transfer device receives the sealing member in the sealing member receiving position and fits the sealing member on a covering end portion of the electrical wire in the sealing member fitting position. An electrical wire insertion guide device is disposed between the sealing member transfer device and the electrical wire clamping device and is slidable along the electrical wire from a lead-out member to the covering end portion. The sealing member transfer device positions a central axis of the covering end portion substantially coaxially with a central axis of the sealing member.