People usually spend 1/3 of the day and night sleeping, i.e., they go to sleep at night and wake up during the day, forming a sleep-wake rhythm. Sleep-wake rhythm disorders are sleep disorders caused by a sleep-wake rhythm that is different from the usual one. The disorder is usually seen in adults, but is rarely seen in childhood or adolescence. Prevention of sleep-wake time disorders: a. Maintain an optimistic, contented and happy state of mind. Have a full understanding of social competition, personal gains and losses, and avoid psychological imbalance due to setbacks. Second, the establishment of a regular daily life system, to maintain the normal sleep-wake rhythm. Third, to create a conditioned reflex mechanism conducive to sleep. Such as half an hour before bedtime hot bath, foot bath, drink a glass of milk, etc., as long as long-term persistence, will establish a “sleep conditioned reflex”. Fourth, moderate physical exercise during the day, to help sleep at night. Fifth, to develop good sleep hygiene habits, such as keeping the bedroom clean, quiet, away from noise, avoiding light stimulation, etc.; avoid drinking tea, alcohol, etc. before going to bed. Sixth, self-regulation, self-referral. Can play some relaxation activities, but also repeated counting, etc. Sometimes a little relaxation, but can speed up sleep. Seven, limit daytime sleep time, in addition to the elderly can be appropriate nap or snooze for a moment during the day, should avoid napping or snooze, otherwise it will reduce the sleepiness and sleep time at night.