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A pickup finger potato precision seed metering device was designed, because of that the traditional cup-belt potato seed metering device had some shortcoming on the seed clamping and seed transport process, and based on the opening, closing, swinging of splint in each process to control the position and movement of seed to achieve five processes of seed filling, seed clamping, seed clearing, seed transport and seed dropping, meeting the requirement of precision planting technology. The structural parameters of key components such as clamping fixture and slideway were designed and the change rule of limiting speed of seed filling and limiting position of seed cleaning was gotten by illustrating and analyzing the overall structure and working principle of each working process of the seed metering device. In order to prove the performance of pickup finger potato seed metering device, the experiment was employed through the method of quadratic orthogonal rotating center combination of three factors and five levels according to national standard (GB/T 6973—2005). In test, potato seed Dongnong 311 was selected as experimental material. Combining with extensive pre-experiment and theoretical analysis, the working speed, seed clearing shifting, length of splint were taken as the main influencing factors, and seed qualified index, multiple index, missing index were taken as the response index, the experimental research was carried out. The optimal combination of parameters were working speed of 6.0km/h, seed clearing shifting of 9.5mm, length of splint of 72mm, and under the optimal combinations, the qualified index was 90.3%, the multiple index was 6.1%, and the missing index was 3.6%, the verification test was repeated five times, the results indicated that the actual test results were in agreement with the optimization results.