The existing slide electrical proportional control valve is difficult to achieve large flow. To solve the problem, a design scheme for a new type of electronic proportional flow control valve was presented, which broke through the slide valve structure. Two electric proportional throttle valve independently controlled were used and the pressures of the throttle import and export were collected by pressure sensors. The pressure-flow joint control of the electric proportional throttle valve was realized by pressure controller. According to the structure of the new electronic proportional flow control valve, the constant pressure difference flow control algorithm under variable load was deduced. The PID control parameters were adjusted by simulation, the program and control algorithm were optimized and the practical value of the program is improved.