The oil-impregnated paper capacitance graded bushing is widely applied in important electrical equipment in power system such as transformers、reactors、switches and so on .In the recent years, the bushing accidents and faults of transformers、reactors and switches occurs frequently, which has aroused relevant departments’ great attention. In this paper, we have introduced the accidents and faults of bushing used in homebred and import transformers、reactors operating in State Grid power system., and given the statistical analysis, meanwhile, through theoretical calculation and structural design, we have done research on simulation bushing test, and mastered the fault reason of oil-impregnated paper capacitance graded bushing.