The lubrication method of high pressure gas has been widely applied in the field of precision machinery. Therefore, stable pressure source with high accuracy for instruments was designed using fuzzy PID algorithm and two series control scheme. The software and hardware of the stable pressure source were introduced. And the experimental results of overall performance of the gas source were analyzed. The results show that: the top argument of the PID parameters is KP=0.6,KI=2,KD=0. Meanwhile, the flow rate within the scope of 5~15 L/min, the system can obtain a more ideal steady state, and the relative error is less than 2%.