Background
: In recent years, the incidence of diseases that related to hyperlipidemia is increased among Korean because of socioeconomic state and diet change. Then, in order to determine the factors affecting serum lipid levels and the cut off value of serum lipid levels by age, we carried out this study.

Methods : Data were gathered through mail questionnaire from 147 adults over the age of thirty who participated in adult health examination from march 1992 to August 1992.
The serum lipid levels were analyzed by sex, age, BMI, income, occupation, education, smoking, drinking, diet, exercise, stress and menopause.

Results : The serum total cholesterol was increased with age in both sex and triglyceride was increased with age in women but not in me. The total cholesterol and triglyceride were more increased in those whose BMI were above 25 than those below 25. Age was more significantly associated with the serum lipid levels than BMI(P<0.01). There is no significant association between age and BMI. Total cholesterol and triglyceride were more decreased in the group of exercise above 3 times/week than below 3 times/week. The total cholesterol was more increased in the group of no-occupation than profession.
The total cholesterol and triglyceride were more increased in postmenopausal women than premenopausal women.

Conclusion : Results of this study may not sufficient to apply affecting factors of serum lipid levels and cut off value because this study group was limited and small. But to know the normal value of total cholesterol and triglyceride, several factors were considered, and further study should be performed.