With the growing use of fossil fuels， energy conservation and environmental protection are facing huge pressure. So the solar energy， wind energy， etc.， which are renewable and clean， have become the focus of the development and utilization in the worldwide. The design of integrated application system for hybrid isolated microgrid including wind power， photovoltaic system， diesel generator， and battery storage （WPDB） was introduced， and the structure of this system and the design method of related subsystems were proposed， under the background of a project in Mozambique. Then， the technical program of battery energy storage system was presented， and the average generating energy of the whole system in 25 years was estimated. The analysis results show that the system can completely meet the application requirements. The proposed design method can provide some theoretical supports and practical guidance to the popularization and application of the WPDB integrated system.