Abstract Background The role of decreasing testosterone levels influencing lipid metabolism in aging men is not well established. Methods We studied 1619 40 to 69-year old men with andropausal symptoms, who underwent measurements of serum testosterone, triglycerides, total-, and HDL-cholesterol. Results Testosterone (mean 15.25 nmol/l ± 5.43 S.D., range 3.6–45.0 nmol/l) correlated directly with HDL-cholesterol ( r = 0.24, p < 0.0001) and inversely with total cholesterol ( r = −0.06, p < 0.03), triglycerides ( r = −0.30, p < 0.0001) and body mass index ( r = −0.34, p < 0.0001), but not with LDL-cholesterol ( r = 0.05, p = 0.09). In multivariate analyses adjusted for age, body mass index, smoking, alcohol consumption, diabetes and cardiovascular diseases, the significant determinants for serum triglycerides were testosterone ( β = −0.03, p < 0.0001), age ( β = −0.01, p < 0.0001), body mass index ( β = 0.039, p < 0.0001) and cardiovascular diseases ( β = 0.09, p < 0.04). The multivariate correlates of HDL-cholesterol included testosterone ( β = 0.007, p < 0.0001), body mass index ( β = −0.02, p < 0.0001) and alcohol consumption ( β = 0.02, p < 0.0001). Conclusions We conclude that in aging men low testosterone levels are associated with a potentially atherogenic lipid profile including high triglycerides and low HDL-cholesterol.