The invention relates to a laser handpiece 1, an exchangeable fiber-optic insert 10, and a control unit 70 therefor. The laser handpiece 1 comprises a optical waveguide 35, which is connected to a light coupling site in a base member 21 and in which the application element 10 for laser light is exchangeably attached to the base member 21. The base member 21 is mounted in a sleeve-type grip 3 for axial displacement therein. The light guide 10 can be wound around a control device 70 which has an annular gap 73 for this purpose and a lower housing part 75 which is offset from an upper housing part 74. An exchangeable fiber-optic insert 10, 27 acting as an application element is provided with a sleeve 80 serving as protection during transportation and as an assembling tool.