How long is considered normal for each sexual encounter? This is a question that we often encounter in our male clinics. When some young people come to our clinic, they tell me that their friends have sex for 20 to 30 minutes, but they only have sex for 4 to 5 minutes, so they suspect that there is something wrong with them, so they come to our clinic. But, is this true? So, how long is normal for intercourse? Before explaining this problem, we should first understand the truth that all of our characteristics as human beings, including walking upright, making and using tools, etc., are the result of millions of years of long-term evolution and the survival of the fittest. In ancient times, the human ancestors of the survival environment is extremely poor, in a very long period of time, the purpose of sexual intercourse is mainly to reproduce offspring, this time, the disadvantage of long intercourse time is revealed. As you can imagine, sexual intercourse is a process of total commitment, if a person’s sexual intercourse time is very long, then, in the event of unexpected events such as beast infestation or enemy attack, he either interrupted sexual intercourse, or be killed and eaten, in short, a result, the possibility of his successful reproduction of offspring is therefore reduced, after millions of years of natural selection, these people were gradually eliminated. Therefore, human development to date, men’s sexual intercourse time are in a reasonable interval. For the specific description of intercourse time, male physicians have a technical term called intravaginal ejaculation latency time, which is the time from vaginal insertion to ejaculation, which is usually 5-15 minutes normal. Also, it should be determined according to the sexual satisfaction of the sexual partner, as well as the psychological condition, the number of successful and unsuccessful sexual life, and other aspects, not to be generalized.