In mass health screening of the inhabitants of a coastal district in Fukui Prefecture, venous blood samples were collected from 304 men (aged 22-87 years) and 223 women (aged 23-84 years). We examined whether serum selenium concentration was related to atherogenic index [= (total serum cholesterol--high-density-lipoprotein cholesterol)/high-density-lipoprotein cholesterol] by multiple regression analysis with age, body mass index, and smoking and drinking habits as independent variables. Atherogenic index was a significant increasing factor of serum selenium concentration in the entire male subjects and the female subjects aged above 60 years.