To simply and inexpensively constitute evacuate control of an atmospheric pressure plasma processing apparatus.

A first evacuation path 41 is drawn out from a suction opening 24 of a processor 20 provided in a processing chamber 10 and connected with an evacuation device, such as a blower 50 via a flow-regulating valve 60. The valve element 62 of the valve 60 is urged in the narrowing direction of the aperture due to the pressure difference between a first port 61a connected with a first exhaust path 41 and a second port 61b connected to the exhaust device 50; while it is urged in the reverse direction by an urging means, such as a spring 64 and thus, it operates so to make the flow rate in the first evacuation path 41 constant. A second exhaust port 42 is drawn out from the processing chamber 10, is equipped with a variable throttle 45 and is connected to the flow-regulating valve 60.