The frequent occurrence of wet dream is mainly caused by human physiological or psychological factors. Physiological problems such as excessive prepuce, prostatitis and urethritis often lead to frequent wet dream. Psychological factors are often caused by sexual psychological problems. For example, long-term excessive sexual fantasies will make the control system of the sexual center in people's brain center gradually tired and reduce the control power, leading to the sexual desire and impulse of teenagers often staying. If forced to suppress, do not slip during the day, it is likely to be left in sleep at night.