Stress affects emotion. The metabolic homeostasis can be influenced by stress stimulated hormones secreted from the body under stress situation. It should be further investigated whether stress correlates with dietary habits and lifestyle as well as the occurrence of metabolic syndrome. The aim of this study is to investigate whether chronic stress correlates with the risk factors of metabolic syndrome, dietary habits, or lifestyle. One hundred and fifty four subjects (79 males and 75 females) aged 38.3±6.8 years were recruited from the Preventive Healthcare Center of the Department of Family Medicine at Taipei Medical University Hospital, and entered the study after signing the consent. Fasting blood was drawn at 8:00~9:30 a.m. within forty-one days. Biochemical parameters, serum cortisol concentration, authropometric assessment, and blood pressure were measured. Meanwhile, questionnaire on dietary habits and lifestyle and the Perceived Stress Scale (PSS) were also collected. The data indicated that serum cortisol concentration was negatively associated with stress score. Serum cortisol concentrations of all subjects and males were positively correlated with systolic pressure, diastolic pressure, and fasting blood glucose when the serum cortisol concentration was the indicator of physiological stress response. Serum cortisol concentrations of the female subjects were positively associated with diastolic pressure, but negatively associated with waist circumference and serum triglycerides. The subjects were divided into the low and high cortisol groups by serum cortisol concentration with the cut point of 9.7 µg/dl. Serum cortisol concentration in the high cortisol group (serum cortisol concentration ≥ 9.7 µg/dl) was positively associated with waist circumference, systolic pressure, and diastolic pressure. Furthermore, serum cortisol concentrations of the males in the high cortisol group showed the positive association with systolic pressure, diastolic pressure, and fasting blood glucose. Serum cortisol concentrations of the females in the high cortisol group appeared the positive association with diastolic pressure. Serum cortisol concentrations of all subjects in the low cortisol group (serum cortisol concentration < 9.7 µg/dl) and males in the low cortisol group were only positively associated with systolic pressure. Furthermore, serum cortisol concentrations of the females in the low cortisol group appeared the negative association with waist circumference. The males had higher waist circumference, systolic pressure, diastolic pressure, and serum triglycerides than the female regardless of cortisol level. However, high density lipoprotein cholesterol level was lower in the males than in the females. The high cortisol group had higher systolic and diastolic pressure than the low cortisol group. However, the females in the high cortisol group decreased waist circumference and serum triglycerides. The dietary behaviors in “you want to eat when your mood is bad”and“you increase food intake due to busy work or external stress”differed significantly between the low and high cortisol groups . In conclusion, the correlation between chronic stress and the risk factors of metabolic syndrome is affected by serum cortisol concentration and gender. Stress is positively correlated with waist circumference, systolic pressure, and diastolic pressure in the high cortisol group (serum cortisol concentration ≥ 9.7 µg/dl), whereas stress is only positively correlated with systolic pressure in the low cortisol group (serum cortisol concentration < 9.7 µg/dl). Furthermore, stress is positively correlated with systolic pressure, diastolic pressure, and fasting blood glucose in the males of the high cortisol group, whereas stress is only positively correlated with systolic pressure in the males of the low cortisol group. Stress is positively correlated with diastolic pressure in the females of the high cortisol group, whereas stress is only negatively correlated with waist circumference in the females of the low cortisol group. However, the relationship between cortisol level (stress level) and dietary habits and lifestyle is not significant in this study. Keysords: stress, cortisol, metabolic syndrome