We examined factors underlying people's willingness to take action in favor of or against nuclear energy from a moral perspective. We conducted a questionnaire study among a sample of the Dutch population (N = 123). As expected, perceptions of risks and benefits were related to personal norms (PN), that is, feelings of moral obligation toward taking action in favor of or against nuclear energy. In turn, PN predicted willingness to take action. Furthermore, PN mediated the relationships between perceptions of risk and benefits and willingness to take action. In line with our hypothesis, beliefs about the risks and benefits of nuclear energy were less powerful in explaining PN for supporters compared to PN of opponents. Also, beliefs on risks and benefits and PN explained significantly more variance in willingness to take action of opponents than of supporters. Our results suggest that a moral framework is useful to explain willingness to take action in favor of and against nuclear energy, and that people are more likely to protest in favor of or against nuclear energy when PN are strong.