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In view of the current 2BDQ maize delta-row seeder high-speed operation (12 ~ 16 km / h) due to the airflow wrapped seeds into the bilateral seed guide device speed is too fast to produce a violent collision, so that the bilateral seed staggered uniformity was decreased, resulting in the problem of low forming rate of the falling seed, a positive pressure air guide groove type seed guide device was designed. The structure of the seed guiding device and the principle of the upper and lower combined seed guiding groove were expounded. The mechanical model of the introduction and attachment process of corn seeds on the guide groove was established, and the relationship between the seed constraint state and the structural parameters of the guide groove during the seed guiding process was explored. The DEM-CFD coupling simulation method was used to analyze the speed trajectory curve of corn seed introduction to determine the width ratio of the upper guide groove and the lower guide groove, and the range of the upper guide groove slotting height, the lower guide groove width and the positive pressure value of the conveying airflow was determined by single factor test. Taking the range of single factor test results as the level value of test factors, the qualified index of glyph and the coefficient of variation of seed introduction consistency as the test indexes, the Box-Behnken design bench test of three factors and three levels was carried out by using JPS-16 high-speed seeding performance test bench, and the optimal parameter combination of seed introduction device was obtained and verified by test. Four kinds of seeds were selected to carry out the suitable sowing test of the device. The results showed that the optimal parameter combination was the upper guide groove slotting height of 354.491 mm, the lower guide groove width of 2.245 mm, and the positive pressure value of the conveying air flow of 0.739 kPa. Under the verification test, the qualified index of the parameter combination was 91.791% , and the variation coefficient of the seed guiding consistency was 6.111% , which was consistent with the optimization results. In the field test, the qualified index of the glyph was not less than 85.1% at working speed of 12 ~ 16 km / h.