Purpose: This study investigated to relationship of fatigue, health promotion behavior and mental health in automotive manufacturing workers. Methods: As a descriptive research design, the data were collected from 198 workers in a city. It was analyzed using the SPSS/WIN 12.0. Results: The level of fatigue was beyond moderate, health promotion behavior was low, mental health was slightly unhealthy. The fatigue was significantly correlated with health promotion behavior. The global fatigue, job satisfaction and drinking explained 22.3% of health promotion behavior. Conclusion: It is necessary for the automotive manufacturing workers and their companies to reduce level of fatigue and mental health and to increase level of health promotion behavior.