Abstract: With the popularity of mobile smart devices and the mature application of 4G mobile Internet technology, as well as people’s demand for fragmented demand and higher media rich content, mobile short video social platforms have emerged. Based on the basic idea of the value co-creation theory, this article takes the short video of Douyin as the case object and adopts the single case study method to study the value co-creation and evolution mechanism of the mobile short video social platform. The studies find out the dominant logic and value co-creation of video publishers, video viewers, and platforms throughout the process. Taking the " subject-activity-output” as the framework, this paper analyzes the main evolution process of the mobile short video social platform in the initial period, development period and maturity period, corresponding main activities, and the output of activities. The research results would help to theoretically understand the value co-creation mechanism and evolution process of the mobile short video social platform, and provide useful lessons for innovative companies and enterprises in practice.