INTRODUCTION: Studies have identified a great number of physiological conditions, including venous thromboembolism and hypoxia, that may give rise to medical disqualifications and in-flight incapacitations that can be costly to individuals and organizations. Over the past three decades, much attention has been focused on venous thromboembolism among passengers. However, studies on venous thromboembolism among commercial airline pilots are very scarce. With this consideration in mind, differently from the literature, this study set out to examine pilots' awareness of venous thromboembolism signs, symptoms, risk factors, and countermeasures.METHODS: For this purpose, a venous thromboembolism questionnaire was developed and applied to collect data. There were 427 airline pilots who participated in the questionnaire. The analysis of variance (ANOVA) technique was used to analyze the results of the questionnaire.RESULTS: According to the results of this study, approximately one-half (57.1%) of the participants had just heard of this particular health issue and 63.9% of the participants were unaware of flight-associated venous thromboembolism. Airline pilots between 20 and 40 yr of age were much less aware of venous thromboembolism in comparison to pilots 41 yr or older, and pilots flying more than 90 h/mo were at a greater risk.DISCUSSION: Airline pilots between 20 and 40 yr have less knowledge about venous thromboembolism and preventive measures against it in comparison to older pilots. Therefore they may be more vulnerable to possible risk factors. The findings of this study will contribute to increasing pilots' awareness on flight-related venous thromboembolism and can improve the overall safety of civil aviation.Kilic B, Soran S. Awareness level of airline pilots on flight-associated venous thromboembolism. Aerosp Med Hum Perform. 2020; 91(4):343-347.