Fuel regulator is an important part to maintain the normal operation of aero-engine.Aiming at the higher requirements of the engine for the fuel regulator response time,according to the structure and principle of the fuel regulator,the main regulating valve was the key component that affected the response time of the fuel regulator was clarified.A new type of main regulating valve was designed according to the hydraulic circuit control principle of the main regulating valve.Finally,theoretical calculation verification and simulation verification were carried out for the new main regulating valve and the traditional main regulating valve respectively.The simulation results indicate that with the duty cycle τ =0% and τ =100%,the response time of new main regulating valve is 0.613 s and 0.843 s,respectively;compared with the traditional main regulating valve,its response efficiency has been improved by 29.5% (duty cycle τ =0%) and 9.06% (duty cycle τ =100%),which meets the rapid response requirements of the engine to the fuel metering system.