Abstract: New type complex photoelectric equipment faces the difficulties such as short of knowledge about the equipment,without experience about equipment's maintainance,etc.In order to improve the technical personnel's capability for equipment's maintainance,the authors try to find methods to construct equipment's structure decomposing model,tactics to carry out fault forecasting,fault multiplying and fault diagnosing in structure member of the equipment.This can enable the technical personnel to master equipment's knowledge rapidly and possess equipment's fault diagnosing capability.