Distribution of potassium content of flue-cured tobacco and factors affecting the distribution in Qianxinan region were analyzed. The results showed that the variation range of potassium content in flue-cured tobacco was from 0.82% to 2.58% with an average of 1.77% in the relative low-potassium tobacco planting area. The potassium content of flue-cured tobacco in Zhenfeng and Xingren counties were much higher than that in Qinlong county, indicating a gradual decreasing trend from the central planting region to the north and south planting regions in the spatial distribution. An extremely significant difference in potassium content of flue-cured tobacco among varieties was observed in which Yunyan87 had a higher level of potassium than Yunyan97. The potassium content increased along with an increase of the clay content and decreased with an increase of the soil organic content. The potassium content increased with an increase of soil pH in the range of 5.0 to 6.5 or above 7.5. The potassium content decreased with an increase of soil pH in the range of 6.5 to 7.5 or below 5.0.