Frequent exposure to appearance ideal social media is associated with body dissatisfaction. We hypothesised that commercial and peer social media literacy would protect against the negative impact of exposure to social media appearance ideal images on young adults' body image. The study was presented as an investigation of alcohol promotion on social media. Participants were 187 women (Mage = 24.6, SD = 3.7) and 187 men (Mage = 22.8, SD = 3.9) who viewed gender-matched alcohol-related appearance ideal social media images or control images containing alcohol only. Social media literacy was assessed prior to image exposure and body satisfaction measured before and after exposure. A negative effect of ideal image exposure on body satisfaction was observed in both women and men. In women only, commercial-social media literacy moderated the negative effect of exposure, independent of internalization or body comparison. Inclusion of social media literacy skills in prevention interventions is supported.