In men without any symptoms of ischemic heart disease, living in two different geographical zones (Moscow and Chuckchee land) low level of high density lipoprotein (HDL) cholesterol was accompanied by alterations in phospholipid composition of HDL2 and HDL3: decrease in the ration of lecithin and increase in sphingomyelin and kephalin content. The alteration in the phospholipid composition of these two HDL subclasses occurred simultaneously with changes in fatty acid composition of HDL lecithin: decrease in the ratio of linoleic acid as well as in stearic and arachidonic or eucosepentaenic acids. At the same time, phospholipid composition of the HDL subclasses was dissimilar in men and women without any symptoms of ischemic heart disease. Role of alterations in the fatty acid composition of phosphatide acid as well as effect of hormones on alterations in the phospholipid composition of HDL in hypoalphacholesterolemia are discussed.