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Aiming to solve the problem of poor seeding quality of the current airsuction vertical disc precision seed metering device caused by higher demands for working pressure during seedfilling process at high speed working conditions. One kind of air suction precision seed metering device with guided assistant seed filling plate was designed to improve the singulation index (SI) of the seed meter at high speed. Basic parameters of the curve were expounded, the source of resistance during the seedfilling was analyzed, and the ideal filling state of the various segments of the seed was presented. An optimal value of the base circle radius of the disturbance groove curve equation was proposed by the calculation of disturbance trough curve equation, the calculation of edge tilt angle, and a single factor simulation experiment was carried out with the CFD-DEM method by gassolid coupling numerical analysis with local void ratio as an indicator. In order to verify the design results, an single factor simulation experiment which compared with two domestic popular airsuction vertical disc precision seed metering devices was carried out under the working wind pressure of -5.0kPa and -6.0kPa. The results showed that the missing rate and the qualified rate were better than those of the other two seed metering devices. Twofactor experiments of operation pressure and forward speed were made on the designed seed metering devices, the optimal operating parameters were proposed by multiobjective optimization analysis. The developed seed metering device was installed on the electrical drive air suction type seeding machine, and the single factor repeating factor test was carried out at three working speeds. When the working speed was 9.11km/h, the grain distance qualified index was 95.48%, and the seedfilling had a better performance at high speed conditions.