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A multilevel shuntmerge distributor was investigated for improving the adaptability of centrifugal precision metering device in the field, especially under some special conditions such as incline and jolt. Some factors those influenced the performance of valvebranch distributor were analyzed. After a quadratic orthogonal rotary regression simulation test by discrete element method software EDEM, a quaternionic quadratic regression model about apiece row consistency variability coefficient of seeding quantity was established. Meanwhile, the optimized distributor was manufactured by using 3D printer. Contrast experiment was conducted by using both direct distributor and branchvalve distributor under the inclined position. The results indicated that, when the branch length of first level shunt cell was 59.95mm, the top length of second level shunt cell was 66.11mm, the angle of shunt cell was 89.74°, the inner diameter of distributor was 7.12mm, and the seeding performance of the centrifugal metering device for rapeseed was very well. Concerning the range of 0° to 25° inclination, apiece row consistency variability coefficient of the device was no more than 5.71%, superior to the direct distributor, and it was also applied to the medium and highspeed planting, and satisfied the agricultural requirements of rapeseed planting.