Abstract: [Purpose/Significance] In the era of big data, people are flooded with massive information, and problems such as knowledge anxiety, adjustment of resource demand structure, and desire for high-quality information follow one after another. From the perspective of technical support, user interaction is rarely explored, but it is indispensable. The application in the field of infrastructure construction and business is relatively complete, but the user interaction of the knowledge service system is still insufficient: at the theoretical research level, there is a lack of summary of theoretical methods and systematic framework design; at the application practice level, there is a lack of systematic guidance. [Method/Process] The agricultural professional knowledge service system has relatively complete and representative user interaction, a large user base, and a high degree of retention, which is worthy of study, but it has certain shortcomings. The research on user interaction of agricultural knowledge system in this paper is mainly divided into the following three aspects. First, by sorting out the research status of user interaction at home and abroad, the user interaction framework of knowledge service system, namely human-computer interaction and interpersonal interaction, constitutes the basic research framework of this research. Second, based on this, using questionnaires and Baidu statistics this paper investigates the user demand of the agricultural professional knowledge service system, and at the same time analyzes the current situation and deficiencies of the system's supply resources, technologies and service layers. Third, this paper proposes an agricultural professional knowledge service system. The user interaction optimization plan starts from the human-computer interaction and interpersonal interaction dimensions of user interaction, analyzes and optimizes the resources, technologies and service layers of the agricultural knowledge system, realizes the friendly interaction of the system, improves the interaction incentive system, and builds a strong interactive knowledge chain community. [Results/Conclusions] The user interaction frame-work of the knowledge service system is designed, and based on this, we analyzed the current situation of user interaction in the agricultural knowledge system, and realized system optimization. The system can better stimulate user needs and understand user needs for the agricultural knowledge system, innovate functions, and provide high-quality personalized services, maintain the attractiveness and participation stickiness of users, benefit more user groups, and play a guiding role in the realization of system upgrades. Due to the lack of relevant knowledge of algorithm technology and lack of technical design for the optimization of agricultural professional knowledge service system, we need to explore the technical layer in the follow-up research; after the system optimization plan is proposed and implemented, experts and scholars need to further test its improvement effect, and propose construction to better realize the all-round optimization of the user interaction of the agricultural knowledge system.

Key words: agricultural knowledge service system, user interaction, privacy protection, questionnaire survey