A laser spark plug configured to be installed into a plug shaft of an internal combustion engine, and to focus laser ignition energy into the combustion chamber via combustion chamber-side, and thus proximal end, of the laser spark plug has, at a distal end of the laser spark plug opposite to the proximal end, a connecting unit for detachable mechanical and thermal connection to a cooler, the connecting unit being designed to permit the connecting and the disconnecting of the cooler when the laser spark plug is installed in the plug shaft.