Abstract:Eight indices from 497 representative soil samples were collected to evaluate the nutrient and fertility suitability of tobacco soil in the Baoshan city, they are, pH, organic matter, alkali-hydrolyzable N, water soluble Cl, available P, available K, available B, available Zn. Member function and principal component analysis were firstly employed to process these data and define the weights of soil nutrients respectively, According to SFI , the city’s soil fertility is divided into five levels (grade I: SFI≥0.70; gradeⅡ: 0.55