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Under the corn-soybean rotation no-tillage planting mode, the corn root-soil combination is large and the ridge distribution is uneven, which hinders the ridge movement of the double-row sowing opener on the soybean ridge, resulting in the uniformity of the seeding depth and the consistency of the row spacing. For poor problems, a double-row sowing opener on a sawtooth soybean ridge was designed. Based on the description of the structure and working principle of the double-row sowing opener on the zigzag soybean ridge, the rake curve was designed, and the rake curve equation was deduced;the mechanical model of the side cutting root system was analyzed, and the side cutting was determined to be sawtooth. The agronomic measurement of the corn root-soil combination determined the key parameters of the sawtooth side edge;according to the agronomic requirements of soybean seeding, it was clear that the seed guide tube in the main body of the opener was arranged in a staggered manner, and the sawtooth opening was determined. The gap angle of the ditch device was 5°. The results of the discrete element simulation verification test showed that the sawtooth opener can effectively cut the corn root system and had better working stability, which verified the rationality of the design idea. Under the conditions of a forward speed of 7km/h and a trenching depth of 50mm, the field performance test was conducted with the root cutting rate as the main indicator. The results showed that the serrated side edge had a strong sawing ability, and the average root cutting rate was 97.25%. Field comparison experiments with double-disc openers showed that compared with double-disc openers, the coefficient of variation of trenching depth was reduced by 43.33%, and the coefficient of variation of transverse seed spacing was reduced by 60.81%. Both the simulation test and the field test showed that the sawtooth opener met the agronomic requirements of double-row sowing on no-till soybean ridges.