A clip includes first and second clamping pieces provided to clamp a member to be fixed. The first clamping piece includes an insertion part to be inserted into a thorough hole of a fixed member. The insertion part includes a pair of strip member, each including a smaller width portion, a larger width portion and a stepped portion provided therebetween. In a course of the insertion part being inserted into the through hole, the larger width portions of the strip members pass the through hole while the strip members are flexed in the direction approaching to each other, and subsequently when the smaller width portions are inserted into the through hole, the strip members are allowed to be deformed in a direction separating from each other to return to an original state, whereby the stepped portions are locked to a region to be locked in the fixed member.