OBJECTIVES: Shift work is a stressful situation. It is important to know the factors associated with the ability to adapt to a shift work schedule. The aim of the present study was to investigate the association between sleep, as well as personality variables, and the resilience of shift work nurses. METHOD: Self-report questionnaires were administered to 95 nurses who worked in one national university hospital. Connor-Davidson resilience scale, hospital anxiety and depression scale, morningness-eveningness scale, Pittsburgh sleep quality index, other sleep-related questionnaires, and Korean defense style questionnaires were used. RESULTS: Age, shift work duration, off-day oversleep, depression, anxiety, adaptive defense style, and self-suppressive defense style were significantly associated with resilience (p < 0.05). Multiple regression analysis showed that age (beta = 0.34, p < 0.05), depression (beta = -0.25, p < 0.05), adaptive defense style (beta = 0.45, p < 0.001), and self-suppressive defense style (beta = -0.19, p < 0.05) significantly predicted the resilience of shift work nurses. Concerning individual defense mechanisms, resignation (beta = -0.20, p < 0.05), sublimation (beta = 0.19, p < 0.05), omnipotence (beta = 0.19, p < 0.05), and humor (beta = 0.20, p < 0.05) significantly predicted the resiliency. CONCLUSION: The findings indicate that a specific defense style and other mechanisms were associated with the resilience of shift work nurses. A future prospective study with more participants could further clarify the relationship between sleep-related variables, as well as personality factors, and resilience of shift work nurses.