We has observed the effects of sex hormones on plasma lipoproteins by analysing 165 patients of non-diabetes mellitus (NDM), diabetes mellitus (DM) and coronary heart disease (CHD) in the elder than 45 years. Of these subjects, NDM were 54, DM 47, CHD 48 and DM with CHD 16. The result statistically showed that is a significant difference in high density lipoprotein cholesterol (HDL-C) and Apolipoprotein A1 (Apo-A1) between male and female subjects in NDM group and general population (P = 0.0001, 0.003 and P = 0.009, 0.002 respectively), but this statistically significant difference could not be observed between male and female patients in groups of DM, CHD and DM with CHD. After adjusting multiple factors of age, body mass index (BMI), estradiol (E2), fasting plasma insulin (FINS), fasting blood glucose (FBS) by the stepwise procedure analysis, the levels of HDL-C and Apo-A1 have significantly negative association with the level of testosterone (T) (P = 0.0012 and 0.0040), however, have no association with E2. Total cholesterol (TC) and triglyceride (TG) have no association with T and E2. The result suggests that T should be an independent risk factor which reduces HDL-C level.