Based on the data of the secondary soil survey of Guangxi province, soil fertility of four orchards, Orange, Litchi, Longan and Mango was investigated in Guangxi province. Results showed that the orchards all deteriorated in soil environment, which was mainly expressed generally in the form of acidification, decreasing organic matter content, lowering ECEC and rising density. For instance, soil pH in the four orchards (Orange, Litchi, Longan and Mango) dropped separately by 0.95, 0.70, 0.89 and 0.64 unit; soil organic matter decreased in content, especially in the Orange and Mango orchards, by 50.63% and 22.45% separately; soil ECEC lowered by 43.64% in the Orange orchard, 30.77% in the Mango and 27.27% in the Longan; and soil bulk density increased by 14 to 37%. As a result of increased fertilizer application, soil N, P and K showed an increasing trend in the Orange, Litchi and Longan orchards, But total N, readily available P and readily available K in the Mango orchard dropped significantly. Integrated analysis of the soil environment and nutrient factors of the orchard soils with the mathematical statistic software-SPSS shows that soil fertility degradates in the Orange, Longan and Mango orchards, especially in the Mango orchard. Thanks to higher NPK application in the Litchi orchard, soil fertility there has somewhat improved.