[Purpose/significance] One important determinant of an successful online social network is the quality of user experience. [Method/process] This paper takes user experience as the starting point,combining multi-discipline to define the user experience in mobile social network. Then,a detailed user experience evaluation system is obtained based on the analysis of the influencing factors of the user experience in mobile social network. Next,the paper uses the analytic hierarchy process(AHP) to weigh the multiple levels of many factors,and based on the dynamic fuzzy sets theory,applies the dynamic fuzzy comprehensive evaluation method to build a dynamic fuzzy comprehensive evaluation model of the user experience in mobile social network. Finally,the paper adopts the dynamic fuzzy comprehensive evaluation model to conduct case analysis on Sina Weibo and Tencent Weibo.[Result/conclusion] The results show that user experience of Sina Weibo is better than that of Tencent Weibo.