A piercing tool (1) can safely and reliably pierce a piercing needle (411) into a skin layer. The piercing tool (1) comprises a belt-like flexible fixing member (2) having an opening (3) formed for raising skin, and a piercing needle moving means (4) mounted on the belt-like fixing member (2) for movably holding the piercing needle (411). By moving the piercing needle moving means (4), the piercing needle (411) is moved so as to be pierced into the skin raised from the opening (3).