Interactive Electronic Technical Manual (IETM) serves as a key supporting technology of aeronautic equipment support informatization and is a carrier for structural, interactive and intelligent equipment technology data. In order to solve the problems that the traditional fault diagnosis system is single in diagnosis-oriented object, low in universality and insufficient in diagnosis knowledge and the like, accurate and efficient fault diagnosis can be performed by virtue of lots of fault diagnosis knowledge in aeronautic equipment IETM. However, knowledge source of the fault diagnosis knowledge exists in various systems of various stages of aeronautic equipment service life, knowledge acquisition model is established with respect to different fault diagnosis knowledge acquisition methods at various stages of study, and isomerism of each system is shielded, thereby realizing resource sharing, improving the fault diagnosis knowledge quality and providing more accurate fault diagnosis service for aeronautic equipment.