The rising prevalence of mobile short video (MSV) addiction among middle-aged and elderly individuals poses a significant threat to their well-being, yet there is a notable paucity of research addressing this critical issue. Drawing on the Stimulus-Organism-Response framework and flow theory, this study examines the relationships between mobile short video characteristics (interactivity, recommendation, and entertainment) and addiction behaviors among middle-aged and elderly users. The research model considers perceived belonging and flow experience as mediating variables, with user habits as a moderating variable. Data were gathered through an online self-administered questionnaire, and structural equation modeling (SEM) was employed for data analysis. The results indicate that recommendation, interactivity, and entertainment are positively related to flow experience, while recommendation and interactivity are positively associated with social belonging. Both flow experience and social belonging are significant determinants of addictive behaviors, with flow experience mediating the relationship between short video characteristics and addictive behaviors, and social belonging mediating the relationship between recommendation, interactivity, and addictive behaviors. Additionally, user habits strengthen the relationships between social belonging and addictive behaviors, as well as between flow experience and addictive behaviors. These findings provide essential insights for designing effective strategies and interventions to prevent and reduce MSV addiction among middle-aged and elderly individuals, ultimately enhancing their digital literacy and quality of life.