Analysis of amplitude-temporary characteristics of the electrocardiogram (ECG) of practically healthy inhabitants of the European North at the age from 20 to 59 years old (n 278) was carried out in order to estimate indices and leads of ECG reflecting the aging changes with a more accuracy. The age dynamics of ECG is more expressed for men with following leads: aVL, III, V4, and aVF while leads aVL and V2 are peculiar for women. An amplitude of the waves S, T, R and P for men as well as R, T and Q for women in ECG was found to change more significantly since the third decade of life to the sixth one. An elongation of the intervals Q-T and R-R as well as the segment S-T is observed in ECG of men and women with ageing of inhabitants of the European North since 20-29 to 50-59 years old demonstrated an appearance of symptoms of hypertrophy of the heart departments, a heart electrical axis deviation to more left position, and delay of de- and repolarisation processes, failed to reach the clinically significant values.