Cabin attendants are mainly responsible for maintaining in-flight safety, and they are crucial to enhance air travel safety and alleviate passenger concerns. The objective of this study is to explore relationships between proactive personality, social support, safety climate and safety behaviors among cabin attendants. A self-assessment questionnaire was used to investigate a sample of 560 cabin attendants from China Southern Airlines Ltd. The results show that proactive personality and safety climate positively influence cabin attendants’ safety behaviors. Social support was found to weaken the positive effect of proactive personality on safety behaviors. Furthermore, social support and safety climate jointly moderate the relationship between proactive personality and safety behaviors, suggesting that this relationship is the strongest when the levels of social support and safety climate are both high. Theoretical and practical implications for researchers and practitioners in designing interventions and strategies to promote safety behaviors in an airline context are discussed.