One of the most robust findings in environmental psychology is that men report lower pro-environmentalism than women. Whilst this difference is often attributed to personality or identity processes, there seems to be a lack of empirical research on potential ideological influences. We propose-and provide evidence through two correlational studies-that radical pro-environmentalism is often akin to propositions of change that challenge tenets of patriarchal ideology such as dominance orientations. As men tend to endorse patriarchal ideologies more than women, they may perceive these challenges as more threatening, leading to greater opposition towards pro-environmental change. In line with our hypothesis, Study 1 (N = 450, UK sample) revealed that men's (vs. women's) greater endorsement of hegemonic masculinity and threat perceptions of anticipated social change accounted for their stronger rejection of pro-environmental policies. Study 2 (N = 254, Francophone Swiss sample) showed that men's greater endorsement of hegemonic masculinity, and higher social and ecological dominance orientation explained their higher perceptions of threat compared to women. These results highlight hegemonic masculinity as a plausible ideological framework likely to bridge previous gender gap explanations and provide policymakers with preliminary insights regarding resistance to change.