The definition of premature ejaculation has not yet been precisely and universally accepted in China and abroad. In 1970, Masters and Johnson defined premature ejaculation as “premature ejaculation when the rate of ejaculation lasting less than 50% of the time during sexual intercourse is sufficient to satisfy the sexual desire of the partner”. In 1984, the Diagnostic and Statistical Manual of Mental Disorders (DSM-III-R) defined premature ejaculation as “ejaculation without desired penile penetration or ejaculation with minimal sexual stimulation. “In 1996, the American Urological Association (AUA) proposed that “premature ejaculation can be considered when one of the two partners is dissatisfied with the ejaculatory latency, or when the male is unable to achieve a sufficiently long ejaculatory latency”. The more accepted diagnosis of premature ejaculation is defined by the DSM-IV-R as “ejaculation before, during, or shortly after penetration, either continuously or repeatedly with minimal sexual stimulation, earlier than the person wishes (in the physician’s judgment, due to various factors affecting the duration of sexual excitement, such as age, sexual partner, sexual environment, and frequency of sexual intercourse), premature ejaculation significantly causes the person The condition is not caused by withdrawal from a psychoactive substance (such as heroin)”. Peng Yifeng, Department of Sexual Medicine, Yiji Mountain Hospital, Wanan Medical College The famous domestic urologist Wu Jieping believes that it is still normal for a healthy adult in his prime to ejaculate at 2-6 minutes of intercourse, or within a shorter period of time. The occurrence of rapid ejaculation at first intercourse is almost a very common physiological phenomenon and cannot be considered premature ejaculation. From an evolutionary point of view, rapid ejaculation in animals has a positive meaning, and the behavior is superior, progressive, and worth encouraging. Because animals are most vulnerable to the dangerous moment of attack by natural enemies during coitus, the shorter the intercourse time, the better for their survival. But in humans, because of the thought and emotion (i.e., love) based on the process of sexual intercourse, the man always wants to give his beloved woman some more sexual pleasure, try to reach the ejaculation time to extend some. And the woman often to their own whether to get sexual satisfaction and orgasm, as a measure of the man’s sexual ability ruler. The definition of premature ejaculation from the point of view of sexual harmony should be “premature ejaculation when the female partner fails to obtain a satisfactory sexual life”. Some women’s orgasms take more than 40-50 minutes to reach, so it’s not scientific to judge premature ejaculation solely on the basis of female orgasm. An image analogy is that men are like light bulbs, a pull on the light, a shut off; while women are like electric irons, always hot after the electricity, once hot, even if the power is off, will not immediately cool down. Sexual intercourse duration and age, physical strength, sexual life experience, sexual intercourse environment and mood are related. The speed of ejaculation is related to the position of intercourse, the amplitude and speed of penile pumping, and the intentional contraction of the female vagina to tighten the grip on the penis. Therefore, the definition of premature ejaculation needs to be further clarified by a large number of well-designed, evidence-based medical studies.