We examined whether internalization of sociocultural body ideals mediated the relationship between conformity to masculine norms and drive for muscularity, leanness, and thinness in a sample of males from Sweden, US, UK, and Australia. Over six hundred young men [n=142 (Sweden); n=192 (US); n=141 (UK); n=160 (Australia)] completed an online survey that included assessments of masculine role norms, body image, and internalization of sociocultural body ideals. Path analyses confirmed internalization as a mediator between greater conformity to masculine norms and body image measures (drive for thinness, desire for leanness, and desire for muscularity) across the sample. However, significant cross-country differences in the strength of these mediation effects were found. Mediation effects among US, Australian, and Swedish males were comparable, whereas these effects were weaker in the UK sample. Findings confirmed the importance of internalization of sociocultural body ideals in the tested models.