Abstract: [Purpose/Significance] Sina Weibo is one of the important social media in the Internet era, and its users play a key role in the development quality of its information services. Analyzing the factors that affect the quality of Sina Weibo information services from the perspective of users will help to improve the information service level, improve the efficiency of information service, and promote the more humanized development of Sina Weibo. [Method/Process] The grounded theory was selected as the research method. Through the process of data collection, three-level coding, saturation test, etc., a model of factors affecting the information service quality of Sina Weibo was constructed. Three factors, namely user base, user experience and user demand, were summarized and their effects on the information service quality were analyzed empirically using statistical methods. The rationality of the model was empirically analyzed by multilevel regression analysis. [Results/Conclusions] The research conclusion shows that user base, user experience and user demand have significant positive effects on Sina Weibo information service quality, among which user base is a guarantee factor, user perception is a key factor, and user demand is a driving factor. To be specific, user base includes user nature, spread scope and interactive experience. A large number of users from a wide range of sources constitute a good online community ecology, which is the fundamental guarantee for the development of Sina Weibo. At the same time, the quality of information service determines the user's experience. Therefore, Sina Weibo should continuously improve the quality of information service to ensure its long-term use. User experience contains user satisfaction and user preference. Specifically, it is reflected in the experience generated by users in the process of using Sina Weibo. Sina Weibo adjusts its information service mode according to users' feelings, so as to improve the quality of information service. Therefore, user experience has a significant positive impact on Sina Weibo information service quality. User demand comprises information authority, information objectivity, information effectiveness, information richness. Specifically, Weibo users tend to pay more attention to public information and have a preliminary judgment on the authority of information according to the identity of the publisher. At the same time, most users hope that the information they publish can be spread widely, which forces the information service quality of Sina Weibo to meet the relevant needs of users. Therefore, user demand has a significant positive impact on Sina Weibo information service quality.

Key words: Sina Weibo, information service quality, user perspective, grounded theory, social media