To address the high rate of grain loss in the two-stage harvest of buckwheat, a pickup-tooth conveyor belt type buckwheat pickup device was developed to mitigate the grain loss in the buckwheat pickup process. The critical components of the pickup mechanism and conveyor mechanism were designed, and the essential parameters were determined. The operational efficiency of pickup-tooth conveyor belt type buckwheat pickup device was verified through field orthogonal test. The field test results indicate that the loss rate is most significantly affected by the speed of the pickup device, followed by the tilt angle of the pickup-tooth. The forward speed of the machine exerts minimal influence. After the multi-objective parameters of the regression equation model were optimized, the optimal parameters of the factors were obtained: the forward speed of the machine of 0.8 m/s, the pickup speed of 1.1 m/s, as well as the pickup-tooth tilt angle of 0°, Under the above condition, the loss rate of buckwheat grain reached 6.92%.