A pattern alignment method performs alignment of the comparison source pattern or the comparison target pattern that has been subjected to the angle-scale conversion with the comparison source pattern. Angular deviations and scale factors between the comparison source pattern and the comparison target pattern are computed separately, after angle and scale conversion, the measured template matching is performed. Therefore, parallel-displacement alignment can be made faster and precise alignment is possible. Template matching processing can be minimized, and aligning can be performed precisely and rapidly.