A sheet-mounting device comprises a loading means (11) including a table (15) on which a semiconductor wafer (W) and a ring frame (RF) are placed and a mounting means for mounting an adhesive sheet (S) onto the semiconductor wafer (W) and the ring frame (RF). The loading means (11) comprises an alignment unit (21) for positioning the wafer (W) by its interaction with a sensor. Since the wafer (W) is positioned in such a state that the wafer is transferred and loaded on the table (15), it is not required to perform the positioning in the previous step.
