The gas laser has a laser gas circuit (5) with a nozzle (4) emitting the laser gas (6), a gas discharge chamber (2) and a cooling system (3a,3b). A bypass (8) is also provided through which part of the gas from the nozzle goes around the discharge chamber (2). Pref. the pressure quotient of the nozzle increases step-wise or is constant with increasing flow volume (V). The nozzle may be a turbo-radial jet. The bypass may connect the pressure side (9) of the nozzle with its suction side (10). The bypass may be located in the housing of the nozzle or may be part of the nozzle. It is preferably possible to be able to switch the bypass on and off.
