Circadian rhythms of 11-hydroxycorticosteroids (11-OHCS) in blood plasma and 17-ketogenic steroids (17-KGS) in urine in health and for 3 days after a single intake of 40 per cent alcohol (6.2 ml/kg) from 17.00 to 18.00 were studied in 20 healthy men volunteers aged 20 to 26 years. Alcohol considerably raised the level of 11-OHCS and 17-KGS during its circulation in the blood. After ethanol elimination was completed, there was a decrease in the level of corticosteroids, which was observed even on the 2nd day after alcoholization during rhythm acrophases. Alcoholization resulted in variations of the mesors, amplitudes and acrophases of circadian rhythms throughout two days. The recovery of normal time structure occurred on the 3d day.