In order to get the better quantitative evaluation of ecological effect in south of Jiangxi Province during nearly 30years, the paper established survey samples ,collected the soil sample and analysed them in the 88typical small watersheds in the south of Jiangxi Province, and then got the following conculsion:①The soil bulk density decreases in polts after the soil and water conservation management, total phosphorus, available phosphorus, total nitrogen, alkali-hydro nitrogen, organic matter content have obviously increased, the physical and chemical properties of soil have been significantly improved; ②The index of the degree of soil improvement has positive correlation with the time of the soil and water conservation management, the longer the management, the better the improvement; ③The effect of soil conservation, protecting fertilizer at contour Zhujie level groove is significant and is worthy of popularizing in soil and water conservation management.