Research suggests that social media use is linked to greater body image concerns and appearance-altering behaviors (e.g., physical activity, anabolic-androgenic steroid use) in men; however, no review has collated these results specifically for men. Thus, the current systematic review examined the relationships between social media and body image (e.g., body satisfaction, internalization of the muscular ideal, selfobjectification), physical activity, and anabolic-androgenic steroid use in men. Six electronic databases were searched. Included studies (N = 60) isolated the male data and reported at least one analysis of the relationship between social media and either body image, physical activity, and/or anabolic-androgenic steroid use. Studies looked at either general social media use, appearance-related social media behaviors, or exposure to social media content. Overall, while some forms of social media (namely, appearance-related) were linked to body image and appearance-altering behaviors, findings were mixed. This was attributed to the diversity and appropriateness of outcome measures for use with men and the type of social media (e.g., time spent on social media, selfie behaviors) used. However, it was clear that appearance-related social media use is related to a more negative body image and greater odds of anabolic-androgenic steroid use in men. Future research should continue to investigate the impacts of social media on men and choose appropriate measures for this demographic.