PROBLEM TO BE SOLVED: To provide a technique capable of preventing a cutting failure in a width direction in manufacturing a fastening tape.SOLUTION: A folding margin portion 174 between a pair of fastening regions is folded like a bag in a lower surface, and then a base material sheet 170 is cut along a meandering cutting line 170c. By doing this, a cutting distance w1 in the width direction of the cutting line 170c is shortened. Thus, a cutting failure easily occurring in cutting in the width direction can be prevented. As a result, the base material sheet 170 can be easily and surely cut. Further, by changing a length w2 in the width direction of the folding margin portion 174, fastening tapes having different lengths can be manufactured using a common cutter.