Irritable bowel syndrome(IBS) is one of the common health problem that has been considered as stress-induced. This study was conducted to investigate the relationship between life style and the level of stress and IBS by structured questionnaire which included questions on life style, the self-esteemed gastrointestinal symptoms, and Psychosocial Well-being Index(PWI). Subjects were 1,498 male white collars who get the regular health check and participated in survey at Inje University Health Promotion Center from January to ,December, 1996. The overall prevalence of IBS was 37.5%(561 cases), and the level of stress by PWI score was higher in IBS group$(41.8{pm}14.2)$ than symptom-free group$(34.6{pm}12.6)$. As the result of comparison between the two groups, heavier smoking (adjusted O.R=2.48, 95% C.I 1.81-3.41), longer daily working time (adjusted O.R=5.19, 95% C.I 3.59-7.56), stimulatory food materials-mainly hot or salty (adjusted O.R=1.87, 95% C.I 1.44-2.45), higher body mass index (adjusted O.R=1.80, 95% C.I 1.27-2.57), and higher level of stress (adjusted O.R=2.81, 95% C.I 1.80-4.43) were estimated as risk factors of IBS. On the contrary, 6-8 hours sleeping per day (adjusted O.R=0.38 95% C.I 0.21-0.70), 3-4 times exercise per week (adjusted O.R=0.57 95% C.I 0.39-0.83), and tenure more than 20 years (adjusted O.R=0.25 95% C.I 0.16-0.35) were considered as protective factors to IBS. In summary, the assessment of the stress level might be placed in the first priority to control IBS, at least by some degree, which suggested that IBS could be controlled by avoiding such risk factors and by encouraging such protective factors.