Abstract:1 242 soil samples were collected in 2015 from tobacco-growing areas in western Hunan, and the suitability distribution, county regional distribution of tobacco-growing soil pH, organic matter, hydrolytic nitrogen, available phosphorus and available potassium as well as the quantitative relations between soil pH and soil nutrients were studied. The results were as follows: 1) Soil pH was generally suitable for tobacco cultivation, with a mean of 6.12. pH of 20.77% of the soil samples was less than 5.0, while pH of 18.20% of the soil samples was greater than 7.5. Mean contents of organic matter and hydrolytic nitrogen were 28.42 g/kg and 145.63 mg/kg, respectively, generally suitable for tobacco cultivation. Mean content of available phosphorus was 28.94 mg/kg, available phosphorus content of about 40% of the soil samples was higher for high quality tobacco cultivation. Mean content of available potassium was 198.76 mg/kg, available potassium content of about 45% of the soil samples was lower for high quality tobacco cultivation. 2) There were extremely significant differences in pH and soil nutrients among different counties. 3) Soil nutrients had curvilinear relationship with pH, when pH<5.5 or >8.0, soil nutrient contents changed rapidly with pH change, but when pH was 5.5–8.0, soil nutrient contents changed slowly with pH change. When pH<5.5, contents of organic matter, hydrolytic nitrogen, available phosphorus and available potassium decreased rapidly with pH increase; when pH was 5.5–8.0, contents of organic matter, available phosphorus and available potassium increased slowly but content of hydrolytic nitrogen decreased slowly with pH increase; and when pH>8.0, contents of organic matter, hydrolytic nitrogen and available phosphorus decreased rapidly but content of available potassium increased rapidly with pH increase.