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No tillage sowing with straw mulch on the surface has social, ecological and economic benefits such as water storage and moisture conservation, improving soil fertility, improving soil structure, controlling soil erosion, reducing production costs and increasing crop yield. In order to solve the problems of poor operation quality and low efficiency of the straw cleaning device under the condition of heavy straw coverage and high speed operation of the no-tillage seeding unit in service, an improved straw cleaning device with the function of straw axial acceleration was designed. The mechanism of the straw cleaning device was clarified, the key components were designed, and the main parameters affecting its working performance and the value range were determined. Using the quadratic regression orthogonal rotation center combination test method, taking the operating speed, operating deflection angle, spiral rise angle and spiral blade number as the test factors, and the straw cleaning rate and working resistance as the performance evaluation indicators, the parameter combination optimization test was carried out on the constructed EDEM-ADAMS joint simulation test platform. The results showed that each factor had a significant impact on the straw cleaning rate, and the significant factors were working deflection angle, operating speed number of spiral blades and spiral rise angle. Each factor had a significant impact on the working resistance, and the significance from large to small was the working speed, working deflection angle, number of spiral blades, and spiral rise angle. The Design-Expert software was used to optimize the parameter combination of the test results. When the helix angle was 40°, the number of spiral blades was 4, the operating speed was 7.5~10.7km/h, and the operating deflection angle was 20.0°~32.5°, the straw removal rate was more than 85%, and the working resistance was less than 110N. Under the operating speed of 8km/h, 9km/h and 10km/h, the field performance test was conducted on the straw cleaning device with a spiral angle of 40°, a number of spiral blades and a working deflection angle of 30°. The straw cleaning rate was more than 82%, and the working resistance was less than 112N, which proved that the simulation test results were credible. At the operating speed of 10km/h, the straw cleaning rate was increased by 33.5% compared with that of the non optimized straw cleaning device, and there was no significant difference in the working resistance.