To realize the needs of the agricultural university’s library information services, and to improve the situation that it is inconvenient for readers to access the resources in traditional libraries, On the basis of the traditional agent model, a multi-agent model was proposed and the personalized information service model was built. The information queried by the users was used as the sample, and the classification algorithm was introduced to classify the pages. The semantic-based user model was built according to preferences of the user’s query and browsing. The main function modules of the model were designed, which included the update method of concepts and the update method of concept weights. Results of this paper are useful for further enhancing the level of intelligence service of agricultural libraries.