In order to reveal the physicochemical properties and their influence mechanism of soil in different rocky desertification in karst area, a four-year monitoring was conducted on soil in different rocky desertification degrees (potential, light, moderate, intensity) before, during and after rainy season in rocky desertification area, Bijie, Guizhou. Physicochemical properties and their correlation characteristics of different soils were analyzed. The results were as follows: in the soils with the same rocky desertification degree, the contents of soil organic matter, total phosphorus, available phosphorus, total nitrogen and hydrolysable nitrogen were all in order as: during rainy season＞after rainy season＞before rainy season. With the deterioration of rocky desertification, soil retention ability, capillary retention ability, capillary porosity and total porosity of soil increased, and the contents of total phosphorus, available phosphorus and organic matter in soil decreased. Compared with the soil in potential rocky desertification degree, total nitrogen contents of soils in light rocky desertification, moderate rocky desertification and intensity rocky desertification increased by 5.6%, 20.9% and 26.6%, respectively, and hydrolysable nitrogen contents of different soils increased by 3.5%, 18.3% and 36.2%, respectively, total potassium contents of different soils increased by 15.8%, 30% and 46.3%, respectively, available potassium contents of different soils increased by 3.9%, 11.3% and 16.5%, respectively. Correlation analysis suggested that organic matter content, total phosphorus content, total nitrogen content, bulk density, total porosity and capillary retention ability correlated significantly (p ＜0.05), and organic matter content, total nitrogen content, bulk density and total porosity correlated extreme significantly (p＜0.01). These results can provide theoretical and scientific basis for the comprehensive control of rocky desertification.