Abstract: Abstract: For promoting pollution-free agricultural products' circulation and improving the service quality of the certified product information, to realize the personalized information retrieval and recommendation of the certified product information, this paper carried out key technology research of the pollution-free agricultural products catalog intelligence services. Employing the product concept, properties, and semantic relations as the principal part, the ontology model of a product catalogue was designed. Moreover, the product directory domain ontology was also set up to form the pollution-free agricultural product electronic catalog. Based on the products catalogue domain ontology, the users' preference feature model was conducted from the ontology concept level. The personalized product catalog weighted ontology model was established based on the concept of weights set by the comprehensive value of the semantic resolution and users' degree of interest. Furthermore, the personalized product catalog weighted ontology establishment algorithm was also designed to realize the dynamic, accurate, and comprehensive description of user interests. Through individual filtering, comprehensive filtering, concept mapping, semantic query expansion, and query result optimization, the recommendation and retrieval algorithm of the personalized product catalog information was constructed to establish the product catalog intelligence service system. In the contrasting experiment of the search results, compared with three used retrieval modes of the retrieval based on domain ontology, the optimized retrieval based on semantic similarity, and the optimized retrieval based on personalized ontology, the degree of the users' satisfaction increased by 31%, 21%, and 14% respectively. The experiment's result showed that the catalog intelligence service system could improve the quality and satisfaction of the pollution-free agricultural products directory information retrieval and recommendation to a certain extent, and met the personalized requirements. Meanwhile, the system also provided the technical support for the promotion, the brand sales, and electronic trading of the pollution-free agricultural product and showed a good prospect for application.