Subjects with normal standard 14 leads EGG were chosen. Relationship of the T loop with blood pressure, serum cholesterol, funduscopic findings, (especialy arteriosclerotic changes) age and sex distriction was studied. Results were as follows. 1) The T loop tended to be small, and circular, and to be located superiorly with the aging in both sex. 2) Location of the polar vector of the T loop tend to convert into the first quadrant froom the second one. 3) The shape of the T loop was not correlated with blood pressure, serum cholesterol and fundoscopic findings and it was more related to the aging. The T loop was large and circular in the forth decade.