Entrepreneurship education (EE) exerts a profound impact not only on the individuals' career trajectories and entrepreneurial activity, but also on organizational innovation and competitiveness, thus being needed to grasp its meaning and consequences further. Drawing on the theory of planned behavior, this study explores the relationship between EE and proactive behavior by examining the mediating role of career attitudes and moderating role of perceived organizational support (POS). Quantitative data were collected from a time-lagged survey of 331 employees in China. Hypotheses were tested via hierarchical regression analysis, following a series of preliminary checks, including common method variance test, analyses of confirmatory factor, reliability, validity, and correlation. The findings indicated that (1) EE is positively related to proactive behavior; (2) two distinct career attitudes, namely, boundaryless and protean, both mediate this relationship; (3) POS enhances both the direct relationship between these career attitudes and proactive behavior, and the indirect effects of EE on proactive behavior via these attitudes. Finally, the theoretical and practical implications for EE and proactive behavior are discussed, and suggested directions for future research.