Metering device as key components of potato mechanization planting has problems including the high multiple index and missing index,heavy manual labor intensity,poor universality and other problems.A new type potato seed-metering device with triangular chain and half-cup was designed.The main structure,working principle and related parameters of the device was introduced in detail.An orthogonal experiment was carried out to understand factors including the driving wheel speed,the inclination of the seed-clearing device and the size of cup affect the performance of the seed-metering device.The parameters were optimized and verified.The results showed that the best performance was obtained when the revolving speed of the driving pulley was 37.5 r/min,the inclination of the seed-clearing device was -5° with the biggest size of cup.The qualified index,the multiple index and the missing index is 93.74%,3.99%,and 2.27%,respectively.The performance of metering device under the condition can meet working performance requirements of the potato seeder.It will provide a theoretical and technical reference for studying and designing seed-metering device of potato seeder.