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One kind of seed metering device with special cells for cole seed was designed. The configuration and working principle was introduced. The differences between two disposal modes of cells were analyzed. And then, the capability, mainly the uniformity of the seed-metering device was tested in experiments. Based on the request of testing result, the structure of the seed-metering device was changed. Some conclusions were given in the end. The disposal modes of cells are the primary factors which affecting the working uniformity of the seed-metering device. Testing with the combination of optimal parameters, the pass percentage of seeding is 98.3%, the leakage sowing rate is 0.6% and reseeding rate 1.1%. Generally speaking, the seed-metering device with special cells for cole seed is simple in structure and steady in working, its cells are compatible with cole seed.