Abstract: Aiming at the problems of low irrigation efficiency of agricultural water resources and confusion of agricultural information management， the expert system of irrigation decision-making and information management with B/S structure was developed on the basis of farmland collection information， meteorological information and basic information， so as to improve the level of agricultural modernization. Based on the structure of the expert system and the irrigation decision of theory， the structure of the expert system was combined with the cloud platform integrating application server and database service， ASP.NET technology of Microsoft .NET Framework and SQL Server 2014 database management system were practical development means to realize the development of expert system application. The results showed that the expert system of irrigation decision-making based on the cloud platform could realize the functions of farmland real-time data monitoring， historical data query and analysis， SMS alarm， data information management and irrigation decision-making， etc. The application program could be accessed well and the data management was convenient. Compared with several experts， it was found that the deviation of the irrigation decision was about ±10%， which met the irrigation requirements.

Key words: water saving irrigation, information management, cloud platform, expert system