To evaluate the relationship between working conditions and workers' health, particularly the effect of work-related stress with change of working conditions for those with alcohol drinking habit and liver disorder, we analyzed physiological examination data and a questionnaire survey including the Japanese version of Karasek's Job Content Questionnaires (JCQ) on work-related stress, working hours, sleeping hours, alcohol consumption and cigarette smoking among male workers of a car manufacturing plant, who engaged in car sales work temporarily and then returned to manufacturing work. In the physiological examination data, the values of body mass index (BMI), GOT, GPT, gamma-GTP, TG and T-CHO rose and the prevalence of obesity and liver disorder increased during the term of car sales work. Comparing the term of car sales work with the term of car manufacturing work, the number of habitual drinkers and heavy smokers increased during the former and decreased during the latter. Increased alcohol consumption and cigarette smoking were also noted during the term of car sales work. Logistic regression analysis showed that the odds ratio of decreasing 'decision latitude (DL)' as work-related stress was statistically significant for increased alcohol consumption. The increased alcohol consumption probably contributing to the prevalence of liver disorder was assumed to be associated with work-related stress due to change of work conditions. Workers who showed liver disorder strongly complained of work-related stress, and it was assumed that the work-related stress was related to liver disorder. Longitudinal observations which take into account work-related stress, alcohol drinking habit and liver disorder must be well planned and personal traits of work-related stress always be taken into consideration.