The purpose of this study was to clarify psychosocial characteristics associated with preventive health behavior for lifestyle-related diseases. The author performed objective health examinations and gave questionnaires to 289 men (39.7 +/- 11.8 years, mean +/- SD) and 80 women (32.8 +/- 10.4 years) engaged in office work. Psychosocial factors included lifestyle and perceived stress, as well as the health locus of control (HLC) and sense of coherence (SOC) as newly developed indicators for health behavior. The principal component analysis for men did not extract lifestyle from the psychosocial structures. Multiple regression analysis showed that internal HLC (IHLC), chance HLC (CHLC), professional HLC (PHLC) and stress significantly contributed to SOC. Principal component analysis using psychosocial factors in women showed two psychosocial structures, i.e. the second principal (high SOC, high lifestyle, and low stress) and the 4th principal components (high supernatural HLC, and high PHLC). Both components were negatively correlated with systolic blood pressure. SOC was recognized to be negatively associated with age, stress, and total cholesterol, and positively with IHLC, FHLC, lifestyle, and gamma-GTP using multiple regression analysis for women. These results indicated a distinguishable sex difference regarding the involvement of psychosocial factors including HLC and SOC in objective health. SOC seems likely to be involved not in objective health, but closely with stress, suggesting a direct influence on mental health. Lifestyle should be divided into more detailed categories such as smoking and salt intake. Structural analysis of women suggests that SOC is involved directly or indirectly through lifestyle in objective health, different from men. To further clarify causal relationships between psychosocial factors and risk factors for lifestyle-related diseases, a longitudinal study is necessary based on these results.