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A large-flow-rate electro-hydraulic control valve was designed by adopting pressure difference feedback rather than displacement feedback, the results of which was cost savings. Elliptical oil ports were designed to reduce the length and mass of the spool to improve the system response speed. For the fact that the response speed of hydraulic valve is affected by the throttling window, a system requiring large flow rate usually adopts large throttling window while a system requiring small flow rate usually adopts small throttling window. However, when the load of a system changes and leads to the change of the system flow rate demand, there is a trade-off between the system stability and speed. Mathematical model of the designed hydraulic control valve was established and simulation results showed that the adoption of composite throttling window could satisfy the demand of speediness in the case of large-flow-rate and the demand of stability in the case of small-flow-rate. And the maximum flow-rate and cut-off frequency of the valve was proved to be 417L/min and 73Hz. A prototype was manufactured and applied to hydraulic impulse testing systems for hose test, the result of which further verified the advantages of the hydraulic control valve.