Across many cultures, women are evaluated based on their appearance, with narrow societal beauty ideals as the standard against which they are judged and, eventually, judge themselves. Women who internalize the beauty ideal are more likely to consider cosmetic surgery. Dissonance-based interventions targeting thin-ideal internalization are effective at preventing eating disorders and associated risk factors. In this study, we evaluated an online dissonance-based intervention targeting beautyideal internalization to reduce favorable attitudes toward cosmetic surgery among Chinese women. Chinese women who were dissatisfied with their appearance and who were considering cosmetic surgery were randomized to the intervention (n=127, Mage =35.49) or to the educational brochure control condition (n =98, Mage =32.97). Beauty-ideal internalization, favorable attitudes toward cosmetic surgery, facial appearance concerns, body satisfaction, and body appreciation were assessed at pretest, posttest, and 4-week follow-up. Intention-to-treat analyses showed that the intervention reduced beauty-ideal internalization and favorable attitudes toward cosmetic surgery at posttest, with small-to-medium effect sizes; however, effects were not sustained at follow-up. No effects were found for facial appearance concerns, body satisfaction, and body appreciation. This study provides preliminary evidence for the short-term efficacy of the dissonance-based intervention for reducing beauty-ideal internalization and favorable attitudes toward cosmetic surgery, and points to valuable directions for improvement.