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Passive stubble-cutting disc with oblique ripple was taken as the object. Based on the method of velocity instantaneous centre, seeder advance speed and in-soil depth of cutting disc were chosen as the main factors affecting stubble-cutting speed. Stubble-cutting depth and draught resistance were the indicators of cutting disc performance experiment, while seeder advance speed and weight assigned to the cutting disc were the experimental factors. Two-indicator and two-factor orthogonal field experiment was carried out for passive stubble-cutting disc with oblique ripples. The results showed that both stubble-cutting depth and draught resistance increased with the two factors, and pullback weight was the principal factor to stubble-cutting depth. When pullback weight on cutting disc reached a certain degree, influence of seeder advance speed on stubble-cutting depth was more prominent than that on draught resistance. 