Abstract: Using the methods of physique test, questionnaire and statistics, the study explores the relationship between the life style and the physical fitness of civil servants in Shanghai. The results show that there are significant correlations between the figures of the civil servants and their life styles including the diet, health behavior, mental stress. It also indicates the significant correlations between the physical fitness and the life styles of civil servants including the sleep, work time and physical activity, health behavior and mental stress. The results of regression analysis shows that the eating habit of meat and vegetables contributes the most to their figures; while the sleep depth and exercise time are the most important indicators of the lifestyle to influence body diathesis of the civil servants.