To tackle the outage cause identification problem and the difficulty in decision-making for power outage judgment of the distribution system，a distribution network outage cause analyzing system is proposed based on fuzzy inference，and its application system is developed.By drawing on the information provided by related systems and the characteristics of the distribution system itself，a hierarchical solving method and the fuzzy abduction theory are used to analyze the outage causes.The system is completed by using the hybrid architecture and the production is deployed on the production command platform.Application in the command of production and emergency repair shows the system proposed is effective and practical.