The results of examination of 21 males and 30 females of the category of elderly and long-lived persons (81--106 years old) indicate the low content in the blood plasma of total cholesterol (173 mg/100 ml), beta-lipoprotein cholesterol (106 mg/100 ml), pre-beta-lipoprotein cholesterol (18 mg/100 ml), and triglycerides (91 mg/100 ml). The average content of these lipid complexes was lower in males than in females. The low concentration of beta- and pre-beta-lipoprotein cholesterol and the large portion of alpha-lipoprotein cholesterol content in relation to the content of total cholesterol in blood plasma are evidence of a favourable proportion of atherogenous and non-atherogenous classes of lipoproteins in blood plasma of elderly and long-lived persons, which is evidently one of the causes of the lower incidence of ischemic heart disease among them and their high longevity.