Gas laser device

A gas laser apparatus, along the gas flow path the blower of the laser gas circulation; detected based on a gas pressure of the laser gas change in speed of the blower, the gas flow path pressure detecting portion; supplying laser gas to the gas passage and from instruction portion instruction to temporarily stop the laser oscillation of the laser oscillator;; a gas exhaust unit for exhaust of the laser gas in the gas flow path and the fan, and a control unit sending a control air supply and discharge unit according to the instructions from the instruction unit. The control unit before the temporary stop instruction portion instruction, at a predetermined speed of the blower rotation, and controls the air supply and discharge section of the gas pressure detecting section detects becomes the first target gas pressure, when the instruction by the instruction section temporarily stopped to reduce sending or stopping the rotation speed of the fan, and the exhaust gas supply section controls the gas pressure detecting section detects becomes the target gas pressure of the second gas pressure when the first target of the blower corresponding to the rotation.