The invention is directed to an improvement of cutting accuracy in a cutting process when a semiconductor device attached with a supporting member is manufactured. The invention provides a manufacturing method of a semiconductor device where a semiconductor wafer (10) attached with a glass substrate is cut with moving a rotation blade along a dicing region and has following features. A pair of alignment marks (51a,b) is formed facing each other over the dicing region on the semiconductor wafer (10). Then, when the rotation blade is to be aligned on a center of the dicing region, that is, on a centerline (61) thereof in the cutting process, positions of the alignment marks (51a,b) are detected by a recognition camera (80), the centerline (61) is calculated based on the detection result, and the rotation blade is aligned on the centerline (61) to perform cutting.