Morning surge in blood pressure is an independent cardiovascular risk factor in the middleaged and the elderly. Whether such a surge occurs in young subjects is not known. Eighty normotensive subjects (age: 21.8 ± 1.3 yr) measured their own blood pressure (BP) using an automatic device (Omron HEM-7080,) on going to bed and on waking up, for 2 consecutive days. In contrast to large morning BP surges reported for older age groups, there was much smaller but significant (P<0.002) rise only in the DBP (1.9 ± 5 mm Hg) on waking up on day 2 in young subjects. The duration of sleep and the time the subjects slept influence the sleep-wake BP change.