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To solve the problems of complex process and low efficiency in rape seeding operation in the rice-oil rotation cropping area in mid-lower Yangtze River, a wide-width folding shallow-rotation combined precision direct seeder for rapeseed was designed, which can realize the functions of opening furrows, shallow rotation, precision seeding of rapeseed, covering soil. The basic structure and working process of the machine were analyzed and determined, and the kinematics and the dynamics analysis on the hydraulic folding mechanism were carried out. The Matlab software was used to determine the structural parameters and the maximum load of the hydraulic cylinder, and the hydraulic folding control system was designed based on the hydraulic oil circuit of the tractor. According to the operational requirements of ditch opening depth, width, plowing depth, and uniformity of soil cover, the speed range of the cutter shaft was 360~480r/min, and the rotation radii of the ditching cutter and shallow rotary cutter roller were determined to be 320mm and 175mm, respectively, the number of ditching cutters was 8. The value range of the structural parameters of the soil dividing deflector was analyzed, the orthogonal test of the uniformity of the soil covering under different structural parameters of the soil dividing deflector was carried out by using EDEM software, and the regression mathematical model of the uniformity of covering soil on the installation distance of the soil dividing deflector, the length of the deflector and the angle of soil dividing plate was established. The simulation test results showed that when the installation distance of the soil dividing guide plate was 200mm, the length of the guide plate was 600mm, and the angle of the soil dividing plate was 60°, the uniformity of the covering soil can reach 93.33%. The field test results showed that when the forward speed of the unit was 3.6km/h, the depth of the furrow was 150mm, and the rotational speed of the cutter shaft was 480r/min, the seed bed crushing rate after operation of the rapeseed wide-width folding shallow-rotating precision combined direct seeding machine was 91.62%, the straw burial rate was 90.72%, the box surface flatness was 13.17mm, and the seedling formation rate was 73.89%. The operation effect of the wide-width folding shallow-rotation combined precision direct seeder can meet the requirements of rapeseed direct seeding operation. The research result can provide a approach for the design of wide efficient seed drill for rapeseed.