Abstract: To achieve better planning of tobacco production in southwestern Guizhou, authors monitored the tobacco leaf quality for several years, and conducted leaf quality regional planning. The authors proposed total sugar and nicotine contents of leaves as partition index for regional planning, and classified them as three levels: high ( total sugar content > 26%, nicotine content > 2.5%), middle (total sugar content 24%～26%, nicotine content 2.3%～2.5%) and low (total sugar content <24%, nicotine content ≤2.3%). According to these criteria, the tobacco leaf quality of southwestern Guizhou could be classified as three zones: the zone with high sugar and low nicotine contents, the zone with high sugar and middle nicotine contents, and the zone with middle sugar and middle nicotine contents. The first zone covers 80% of tobacco production area in southwestern Guizhou, the second zone covers 20%, and the last zone had tobacco production years ago and needs to be developed for tobacco production.