Balanced samples from 12 countries (N= 12,000) were surveyed about their reasons for valuing nature and pro-environmental behaviors. Results showed that people were least likely to endorse moral-based reasons for valuing nature, as compared to five other reasons (wellbeing benefits, nature’s intrinsic value, health benefits, economic value, identity-based reasons). However, moral- and identity-based reasons (relative to the other four reasons) for valuing nature were the strongest predictors of pro-environmental behavior across three different methods (correlations, linear mixed models, and relative importance analysis) and two pro-environmental behavior categories (consumer behavior and activism). In other words, the reasons for valuing nature most associated with pro-environmental behavior also garnered the weakest support, presenting a potential dilemma for those hoping to leverage values to promote pro-environmental behavior. We also identify a possible mechanism (awareness of one’s environmental impact) to explain why moral- and identity-based reasons for valuing nature best predict behavior. Finally, we examine between-country variability in the endorsement of the six reasons and the reasons’ associations with pro-environmental behaviors, and country-level factors that may explain between-country variability in these outcomes. We discuss these results in the context of broader literature that has focused on an intrinsic vs. instrumental valuation of nature dichotomy.