Abstract: The invention is directed to a guide bar for portable motor-driven chain saws. The guide bar includes two steel side parts and a center part connected to the side parts. The weight of the guide bar is kept optimally low while at the same time providing adequate stability and the longest possible service life by providing cutouts extending in the longitudinal direction which are provided with a filler of a material having a lower specific gravity. The cutouts of the side parts and the cutout in the center part filled likewise with a lighter material are arranged so as to not coincide with each other when the guide bar is assembled. In this way, a form-tight mounting for the filler is formed in the side parts and in the center part.