The main causes of premature ejaculation in men are the following: 1. Consider that the patient is suffering from prepuce or prepuce, these two diseases can easily cause premature ejaculation in patients, which can be treated by circumcision; 2. Consider that the patient’s body has organic lesions, such as prostatitis, vesiculitis, such diseases reduce the excitement of the central nerve in the brain, which in turn triggers premature ejaculation in patients; 3. The patient’s excessive and frequent masturbation has developed the habit of ejaculating within a short period of time, causing the patient to suffer from premature ejaculation; 4. It is also necessary to consider whether the patient has been in a state of high mental tension for a long time, and excessive tension when the patient has sex can also cause premature ejaculation; 5. It may be due to excessive sensitivity of the glans. All of the above are possible causes of premature ejaculation, in addition to if the patient wears underwear that is too tight, increasing the irritation of the glans, which may also cause premature ejaculation in the long run.