The rapid development of the mobile Internet era has given rise to various new forms of digital entertainment. Among them, the short video platform is deeply loved by users for its relaxed, vivid, and intuitive characteristics. Among the many short video platforms, TikTok has become a leader in the trend with its innovative content presentation method, extensive user group, and good user experience. TikTok platform provides a vast platform for users to choose their favorite video types and speak freely.This study aims to deeply explore the usage characteristics and psychological motivations of TikTok users by applying the "Uses and Gratifications Theory" framework, to provide a deeper understanding of the development and user experience of the short video platform. Among them, TikTok is represented. This study analyzes the audience's usage preferences based on the "Uses and Gratifications Theory" and further studies the psychological motivations of TikTok users of different age groups through interview methods.