Abstract: The combustion heater is a key part of the ground testing facility for the research on scram jet.The main test gases ingredients include hydrogen, oxygen, air and nitrogen. The pressure and flow of these test gases ingredients need to be regulated during testing, and the pressure is controlled directly by the air-driven valve. A control system with a industrial control computer as it's central part is designed, and a good balance between the reliability and the prac-ticality of the system can be achieved. According to the characteristics of the air-controlled valve, a kind of adaptive Fuzzy-PI controller is designed to realize the fine pressure control during test. It is realized by connecting the conventional PI controller with a parameter regulator which adjust the integrator and proportion parameter of the PI controller through fuzzy inference during test. It has improved the pressure control precision with some good qualities such as quick response, less over-regulating and less stabilizing time.