Achievement motivation encompasses a well-establish distinction between the motive to avoid failure (e.g., fear of failure) and the orientation to improve competence (e.g., mastery goal). But how well do they generalize across cultures in understanding students’ performance and well-being? We argue that students’ achievement motivation is less pronounced in societies characterized by low (vs. high) social mobility, where people have fewer opportunities to change their social status. To test this hypothesis, we analyzed a cross-national data set ( n = 498,362 high-school students from 65 regions) using multilevel modeling. The results indicated that societal-level social mobility significantly moderated the role of (a) mastery goals and fear of failure on academic performance and (b) fear of failure on well-being. These associations were stronger in societies with high (vs. low) social mobility, suggesting that students derive greater academic benefits from mastery goals and fear of failure in societies with higher social mobility. In such societies, however, fear of failure also poses a stronger hindrance to students’ well-being. These findings highlight that the same type of motivation may operate differently across cultures and that socioecological environments may influence the motivational impacts on learning and well-being.