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The large amount of surface straws in the no-tillage planting process results in dragging and piling and the ground temperature rises slowly after planting under the conditions of conservation tillage and straw returning to the field in the black soil area of Northeast China. Aiming at the problems, a method that the straw was crushed and deep buried in the strip was proposes, that was, the surface straw was picked up and crushed by the picking and crushing mechanism, the soil and straw screening was completed by the sieve holes at the cover, the stalk collecting spiral performed the directional collection and transportation of the straw, and finally the straw was transported and buried deeply by the straw conveying fan. The key parameters such as the structure, arrangement and speed of the crushing knife were designed, and the straw leakage area of the crushing knife shaft was analyzed. Through theoretical analysis and discrete element single factor simulation experiments, the relationship between the speed of the stalk screw and the torque and the speed of the stalk movement was clarified, and the speed range of the stalk screw was preliminarily determined to be 900~1100r/min and the structural parameters of the ditching shovel was designed. And the discrete element full factor simulation test was used to simulate the relationship between the operating speed and ditching depth and the movement of surface soil particles and the force of the ditching shovel, taking the operating speed, ditching depth and stalk collecting spiral speed as factors, the Box-Behnken test was carried out with the qualified rate of straw buried deep as the test index. The field test results showed that when the device’s forward speed was 3km/h, the trenching depth was 290mm, and the spiral speed was 1000r/min, the straw burial pass rate was 64.2%, and its predicted value was about 67.4% under the similar parameters. The error was less than 5%, which met the design requirements of the device. The method results can provide a scheme and technical support for the promotion of conservation tillage in the black soil area of Northeast China.