In order to explore the impacts of eco-environment changes on the soil structure and anti-erodibility in the conversion of farmlands to Eucalyptus grandis plantations, soil samples of 4.5-year Eucalyptus grandis plantations such as pure Eucalyptus grandis, Eucalyptus grandis+grain crops, Eucalyptus grandis+fruits were chosen as researching materials and farmlands as comparison, the fractal characteristics of soil water-stable aggregates and the relationship among soil nutrient, soil stability and anti-erodibility were carried out based on the field investigation and lab analysis. The results showed that the different patterns had different fractal characteristics, the fractal dimension was between 2.142 to 2.296. In the soil depth of 0-15 cm, the order of fractal dimension was farmland > Eucalyptus grandis+fruits > Eucalyptus grandis+grain crops > pure Eucalyptus grandis. There was a significant difference between the farmland and pure Eucalyptus grandis, instead of the other 3 types. In the soil depth of 15-30 cm, the order of fractal dimension was farmland > pure Eucalyptus grandis > Eucalyptus grandis+grain crops > Eucalyptus grandis+fruits, and there was no significant difference among 4 types. The fractal dimension had a significant negative linear correlation with organic matter, big soil water-stable aggregate, and a negative linear correlation with mean weight diameter of water stable aggregate and water stable index. On the contrary, it had a significant positive linear correlation with soil bulk density and micro-aggregate. Furthermore, the smaller the fractal dimension was, the higher the content of organic matter and the big soil water-stable aggregate, the bigger the mean weight diameter of water stable aggregate and the water stable index, the lower the soil bulk density and the micro-aggregate, and the stronger the anti-erodibility of soil water-stable aggregate. In the other word, the fractal dimension can be used as an important parameter for characterizing the soil structures and properties, also can be used as an indicator of soil anti-erodibility of the different Eucalyptus grandis plantations.