Objectives: The number of elderly workers has also been increasing and poor psychological wellbeing in elderly workers has been reported. The aim of this study is to elucidate the factors that are related to poor psychological well-being in elderly workers.Methods: We administered General Health Questionnaire-12 (GHQ-12) as an indicator of psychological well-being to 330 male elderly workers in the age range of 50-69, and analyzed different psychological factors, namely sense of coherence (SOC), and physical and lifestyle variables such as blood pressure, serum total cholesterol, smoking frequency, alcohol intake, exercise frequency, and body mass index (BMI) that are related to GHQ-12.Results: When the cut-off point of GHQ-12 was 2/3, 97 workers who showed high GHQ-12 score were classified as one group having poor psychological well-being. A statistically significantly lower SOC score, higher stress score, lower frequency of exercise, higher smoking score and higher BMI, but not longer working hours or higher shift work score in the workers with higher GHQ-12 scores were observed than in the workers with normal GHQ-12 scores. Multiple logistic regression analysis showed that the low SOC score, low frequency of exercise, high smoking frequency and high BMI significantly contributed to the high GHQ-12 score.Conclusions: A low SOC score in elderly workers is assumed to be directly related to poor psychological well-being, or via the development of lifestyle problems such as lack of exercise, obesity, and smoking in elderly workers. This assumption must be confirmed by conducting future intervention studies on lifestyle.