Abstract: A filament-type trimming apparatus comprises a reel case including a main body and a bottom member, a cord reel housed in the reel case and which is wound with a nylon cord, plural stoppers on a lower surface of the cord reel and on an inside of the bottom member and which become engaged when the cord reel is pressed downward by a coil spring, a mechanism for releasing a centrifugal force of the cord reel and which is provided between the cord reel and the bottom member and which comprises radial guide grooves and balls arranged inside the guide grooves, and plural stoppers on an upper surface of the cord reel and on an inner surface of the reel case respectively and which become engaged when the cord reel is pressed upward resisting against the pressing force of the coil spring. A boss is provided inside the reel case main body at its center and to which the coil spring is fixed.