A clip includes a pin; and a grommet including an insertion hole where the pin can be inserted, and forming a plurality of leg pieces by a slit provided in a length direction of a leg portion. In the clip, the grommet can spread portions by inserting the pin into the insertion hole. A prevention portion, which prevents a foreign matter such as gravel and the like from entering in, is provided at least in either one of the pin or the grommet (for example, the pin). The prevention portion may be positioned in one portion of an insertion leg of the pin, or positioned in one portion of the leg piece of the grommet, or provided to extend along a length direction of the slit from a lower surface of a flange of the grommet.