Social media has become increasingly significant in life with its convenience and communicative vividness, shaping users' perceptions and reinforcing social norms, including socially accepted beauty standards. In China, the development of domestic social platforms has fueled a desire for achieving thin or muscular ideal bodies. Bariatric surgery, a procedure on the digestive system with substantial post-surgical weight loss, enjoys great popularity for individuals concerned about weight and shape. Given that prior studies have primarily explored the relationship between social media use and willingness for bariatric surgery in Western settings, a notable gap exists regarding this association in the Chinese context. Drawing upon social learning theory and social comparison theory, the current study aims to pioneer an investigation into social media’s impact on Chinese individuals' willingness for bariatric surgery and its underlying mechanisms. Unlike previous studies that evaluated social media use by duration, the researcher innovatively assesses social media use from multiple dimensions: intensity, appearance-related preoccupation, and photo-based activities. Using a quantitative approach, a cross-sectional survey involving 385 Chinese participants who use Chinese social platforms and have body weight or shape concerns was conducted. Results reveal a positive relationship between social media use intensity and photo-based activities with willingness for bariatric surgery, while the effect of appearance-related preoccupation is insignificant. Psychological mechanisms include upward social comparison, body dissatisfaction, body ideal internalization, and low self-esteem. While this study primarily focuses on direct relationships, it leaves room for future exploration of mediation and moderation. These findings address the literature gap on how Chinese individuals perceive and contemplate bariatric surgery under social media influence. The study suggests preventive interventions through promoting rational social media use to alleviate body image concerns and disseminating accurate information about bariatric surgery.