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In order to improve the speed stability of the hydraulic drive tractor and the ride comfort at low speed, a hydraulic proportional flow valve was designed. Pressure compensation function was used to eliminate the iMPact of pressure fluctuations on the flow. The structural parameters of the valve were designed by the method of traditional calculation and simulation. The simulation results showed that the flow rate range was 0~5.67×10-3m3/s and the flow rate was changed smoothly with the change of control pressure;the flow rate control pressure zone accounted for 68.4% of the total control pressure range;the range of the compensation pressure was 0.3~0.7MPa. The test results showed that the flow rate control pressure zone accounted for 45% of the total control pressure range when tractor was no-load and at idle engine speed;the flow rate control pressure zone accounted for 62% of the total control pressure range when tractor was no-load and at high engine speed;the flow rate control pressure zone accounted for 49.5% of the total control pressure range when tractor was high-duty and at idle engine speed;the flow rate control pressure zone accounted for 48.5% of the total control pressure range when tractor was high-duty and at high engine speed;the flow rate of the valve was stabilized at 8.33×10-5m3/s when the control pressure was set to be 0.78MPa and it was stabilized at 2.5×10-4m3/s when the control pressure was set to be 0.84MPa.