It begins to realize that expert system is used in many hydrauiicsystem and components . this thesis provides the base for the further studying on expert system of hydraulic faultdiagnosis and enhances the efficiency and accuracy for hydraulic fault diagnosis inagricultural machine 本系统搜集了大量的农机液压系统的故障信息，具有很高的使用价值，首次实现了专家系统在多种农机液压系统及其元件故障诊断中的应用。
