The invention discloses a fast follow-up control algorithm of a pressure adjusting valve. A controller, an actuator, the pressure adjusting valve and related sensors are included. The pressure, temperature and flow sensors are installed in front of the pressure adjusting valve. An interference source comes from another valve. The control principle of the fast follow-up control algorithm of the pressure adjusting valve is as follows: 1, after disturbance happens, the controller detects a flow signal and a valve position signal of the interference source; 2, the controller obtains a KV value ofthe pressure adjusting valve according to an engineering thermodynamics calculation formula, then flow characteristic curve value checking of the adjusting valve is performed, and valve position opening degree information of the corresponding KV value is obtained and serves as flow feedforward inhibiting interference; 3, meanwhile, interference source valve position changing is extracted, and serves as valve position feedforward instantaneous disturbance; and 4, comprehensive effects of flow feedforward, valve position feedforward and closed loop adjustment act on the actuator, and opening andclosing of the pressure adjusting valve are controlled. The fast follow-up control algorithm of the pressure adjusting valve is extremely good in control effect, and extremely good in response characteristic and stability, meanwhile, a universal debugging method is adopted, the debugging task is greatly relieved, and very high reliability and adaptability are achieved.