Using data from 46 economies over the 2007-2022 period, this study investigates the impacts of female political participation on environmental performance measured by CO2 emissions. Our main results show that female political participation helps to reduce CO2 emissions, and these results remain robust to various specifications. We further explore two mechanisms by which female legislators can influence environmental quality. The first mechanism is through environmental regulations. It is found that, in the long term, female political participation improves environmental quality by increasing the prevalence and stringency of environmental regulations. The second mechanism is through environmentally friendly policies, and we find that, in the long run, women’s political participation can improve environmental performance by facilitating renewable energy consumption and promoting the development of green finance. Lastly, we also show that the levels of economic development, governance quality, and social progress can enhance the beneficial effects of female political participation on CO2 reduction.