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In order to solve the problem that the seed groove opened by furrow opener is narrow and can not adapt to the wide seedling belt of oats in sandy loam soil, based on the working principle of sliding cutting, a type of furrow opener for oat sowing was designed which can realize wide seeding belt and reduce resistance. The working principle of the furrow opener was described and the curve equation of the cutting edge was determined. The main structural parameters of the retaining surface were determined by analyzing the working resistance of the retaining surface and the cause of the seed trench with wide seedling belt. The EDEM simulation analysis method was used to carry out the ternary quadratic orthogonal rotation combination test with the operating resistance of furrow opener and the variation coefficient of seed groove width as the test response indexes, and a credible regression mathematical model was obtained. The effect of the interaction of various factors on the performance of the furrow opener was analyzed. Using genetic algorithm NSGA-Ⅱregression mathematical model for multi-objective optimization, and taking soil bin as verification test, it was concluded that the optimal parameter combination was as follows: the sowing depth was 41mm, the angle of penetration was 24°, and the width of the furrow opener was 107mm. At this time, the operating resistance was 727.1N, and the variation coefficient of the seed groove width was 9.92%. The average value of the working resistance obtained from the soil bin verification test was 789.07N, the average variation coefficient of seed groove width was 10.69%, compared with the optimization results, the errors were 8.52% and 7.76%, respectively. The results showed that the working effect could meet the agronomic requirements of wide seeding zone oat planting.