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A directional seed-feeding mechanism combined with cell-type seed-metering device was developed to meet the precision planting requirement for low sowing quantity for non-round seed. The working principle of directional seed-feeding mechanism was analyzed. The motion model of a seed in the directional seed-feeding mechanism and dynamic model of a seed filling into a cell was established and the parameter design of the key structure was completed. The quadratic regression rotational orthogonal experiments were carried out with the installation angle of V-groove, vibration direction angle, vibration frequency, voltage (amplitude) and the rotational speed of seeding wheel, and multiple regression analysis and response surface analysis of experimental data were carried out by using Design-Expert 806 software. The regression model between the factors and qualified rate was established and the influences of factors on indexes were analyzed. The influence relation of factors on the qualified rate was determined and the order of importance was vibration frequency, amplitude, vibration direction angle, installation angle and wheel speed in turn. Based on the regression model, the parameters were optimized and the experimental verification was worked out. Results showed that the optimal parameter combination of installation angle, vibration direction angle, vibration frequency, amplitude and wheel speed was 4.02°, 31.29°, 35.9Hz, 4.03V and 5.55r/min, respectively, and the qualified rate and the leakage rate of experimental verification was 97.64% and 2.36%, respectively. There were no more than three grains per cell. The device can meet the requirements of precision seeding for low sowing quantity. It was feasible that cell-type seed-metering device combined with the directional seed-feeding mechanism realized precision seed-metering of non-round seed.