Abstract: Based on analyzing the object-oriented language feature and exception handling mechanism,this paper make some improvements to traditional system dependence graph(SDG),realize Object-oriented system dependent graph(OSDG).The improved OSDG can clearly describe some complex problems for object-oriented languages such as inheritance,polymorphism and deal with data and control dependence for the exception thrown out,and exception treatment from polymorphism object.Through the traditional slicing algorithm,more accurately slice can be gotten.