A sheet adhering apparatus (10) is provided with a sheet feeding unit (12) for feeding an adhesive sheet (S) to a position facing a plane of a semiconductor wafer (W), and a pressing roller (14) for adhering the adhesive sheet (S) on the wafer (W) by pressing the adhesive sheet (S). The sheet feeding unit (12) includes a tensile force measuring means (35) for measuring a tensile force of the adhesive sheet (S) between the sheet feeding unit (12) and the pressing roller (14) and an adhering angle maintaining means (37) having a feeding head (49) for maintaining an attaching angle (theta). Afteradjusting the tensile force by measuring the tensile force just before adhering the adhesive sheet (S), the feeding head (49) is brought down in proportion to a moving quantity of the pressing roller(14) to maintain the adhering angle (theta), and the tensile force is kept constant.