A clipping device including a pin and a grommet, the pin including an engaging groove, an enlarging groove, the grommet including a flange part and a body part, the body part being divided into a plurality of divisional leg portions interposing slits, inwardly directed projections being formed on respective inner faces of the divisional leg portions, wherein the pin is provided with a stepped part on its upper end edge, and a swinging piece which is connected to a side face of the divisional leg portion so as to swing in a horizontal direction is provided in the slit of the grommet, the swinging piece being projected outwardly from the body part of the grommet while it is in a free state, and adapted to be pressed by inner peripheral faces of panel holes when inserted into the panel holes.