Research on environmental concern has consistently found that women have modestly stronger pro-environmental values, beliefs, and attitudes than do men. Scholars have proposed and examined several explanations and have found that only a few hypotheses receive somewhat consistent empirical support, including the institutional trust hypothesis. Given that recent research suggests that men and women have equivalent levels of trust in social institutions, we chose to revisit the institutional trust hypothesis. We use a structural equation modeling technique on General Social Survey data from 2000 and 2010. In both years, we found that women report greater pro-environmental views and concern about environmental problems than do men. Yet, we found only minimal gender differences in institutional trust and no evidence that institutional trust mediates the relationship between gender and environmental concern. Our study does not support the institutional trust hypothesis. We end by identifying potential implications of our findings and suggestions for future research.