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During the process of maize production in brown soil in northeast of China, the method of deep burial straw returning can break the plow pan, increase the fertility of deep soil, store water, retain soil moisture and construct a reasonable plough layer structure. Besides, it also solved the problem of effective treatment of straw. The 1JHL-2 type deep burial straw returning machine can complete crushing, collecting, trenching and burying operation of straw that covered the surface at one time. In order to solve the problems such as large ditching resistance, uneven force of whole machine and poor linearity of advancement, the parameter optimization design was carried out on spiral type opener. For the problems of sticking with the soil and blocking easily during ditching, bionic optimization design was applied on the spiral blade surface. Through the kinetic analysis on spiral type opener device, the optimal structural parameters were finally determined. Taking the deep burial rate of straw, power consumption of trenching and maximum deviation of straight travel of the machine as experimental indexes, the forward velocity, rotate speed of spiral type opener and ditching depth as experimental factors, quadratic regression orthogonal rotational combing design with three factors was also used. The experimental results showed that forward velocity of 1.04m/s, rotate speed of 275r/min and ditching depth of 28.5cm were the best parameter combination of working performance. With the optimal parameter combination, the average rate of straw deep burial reached 92.03%, the average power consumption of trenching was 17.7kW and the maximum deviation of straight travel was 74mm, which were verified experimentally in field and met the technical requirements.