Abstract: [Purpose/Significance] The existing research on the subject of readers' recommendation lacks in-depth discussion on the reasons for readers' recommendation. This paper analyzes and interprets the reader's recommendations from a new perspective in order to explore the multiple values of reader recommendation and purchase services, and build relevant theoretical models. It provides a theoretical basis for giving better play to the role of reader recommendation service. [Method/Process] In recent years, grounded theoretical application has attracted much attention of more and more scholars. It is also considered to be a reliable and effective data processing and analysis method in the field of library and information science (LIS), which is especially helpful to improve the effectiveness of user based qualitative research. This study uses the research method of grounded theory to analyze the "recommendation reasons" based on the reader's recommendation data. We extracted and conceptualized the main meaning of the data, refined corresponding concepts and categorized them level by level, and integrated the relevant concept categories and their attributes, using the iterative research strategy to compare the data and concepts back and forth, considered the relationships between them, and linked these relationships in some way, from which we can conclude and deduce the interrelated concept categories, and then developed into a theoretical concept. On this basis, the promotion mechanism model of user demand to library literature resource construction, management and service is established. [Results/Conclusions] The information contained in the reader's recommendation data has a variety of values. The in-depth study and utilization of the recommendation information will help the library correctly evaluate the relationship between resource allocation and service allocation, and promote the library to improve its overall service level in resource construction, resource management, resource service and other aspects. There are still some shortcomings in this study, which is also the research direction in the future: only the recommended information of readers on printed book resources was selected as the research sample, and the resource type was relatively limited; there was lack of in-depth discussion on the feedback mechanism of readers' recommendation. Reader recommendation is a long-term service provided by university libraries. In the future, in combination with paper literature resources and electronic literature resources, and with the trend that electronic literature resources and open access literature resources become more and more abundant, we should carry out a survey on the comprehensive service of readers' recommendation of various types of resources, and further explore the interactive mechanism of readers' recommendation and recommendation feedback.

Key words: readers' recommendation, reason for recommendation, grounded theory, university library, resource construction