Abstract: Abstract:【Objective】Based on screening from 86 cotton cultivars (Gossypium hirsutum L.), different responses to potassium stress between high K-efficiency and high yield potential cotton genotype103 (HKHP103) and low K-efficiency and low yield potential cotton genotype 122 (LKLP122) were studied.【Method】The research carried out by using pot experiment at different K levels (-K: 0.0 g/Kg and +K: 0.4 g/Kg).【Result】The result showed that HKHP103 grew much better than LKLP122. Only down leaves appeared Potassium deficiency symptoms for HKHP103, but to LKLP122, all of up、middle and down leaves appeared potassium deficiency symptoms. Dry matter weight was also different between them. Root dry matter weight of HKHP103 was 1.07 and 1.25 times of LKLP122 under －K and +K conditions, Which showed that the root of HKHP103 developed better than that of LKLP122. At －K and +K treatment, the main shoot of HKHP103 was 1.13 and 1.07 times of LKLP122, which showed that HKHP103 had a strong transport organ. The distribution of dry matter and potassium was mainly to boll organ for HKHP103, the boll dry matter weight of HKHP103 was 2.58 times of LKLP122 at －K treatment, and 1.90 times at +K treatment. As for potassium accumulation in boll, HKHP103 was 1.98 times of LKLP122 at －K treatment, and LKLP122 was 49.6％ of 103 at +K treatment. Boll was a propagation organ, but for vegetable organs, the distribution of dry matter and potassium was very little. As a result, 103 had an ability to transport and distribute the organic matter and accumulated potassium effectively, and its rate of K utilization was about 2 times of LKLP122. 【Conclusion】The reason why 103 was a high K-efficiency and high yield potential cotton genotype was due to its ability of high absorption、transportation、distribution and utilization for organic matter and potassium.