The most basic test to assess male fertility is semen analysis, so whether the semen collection is correct will affect the accuracy of the semen analysis results, thus affecting the diagnosis and treatment of infertility. The following are precautions regarding semen collection: 1. Abstinence from sex for 2-7 days before semen collection, and no masturbation, dreaming, etc., smoking and alcohol cessation, and avoidance of drugs that affect spermatogenesis. 2, before taking sperm with warm water will wash hands, pubic area, especially the glans; can use masturbation method or electric massage ejaculation method to take sperm, avoid interruption of sexual intercourse or condom to take sperm, because vaginal secretions will contaminate semen, condoms have spermicidal ingredients, affecting the quality of sperm. 3, the discharge of semen has a certain order, the beginning part from the prostate, epididymis, accompanied by a large number of sperm, the last part from the seminal vesicles, so the complete semen should be collected, do not miss any part, especially the beginning part. It is because the first part of the semen is easily lost, so the semen cannot be collected by the in vitro ejaculation method. 4. The container of semen should be clean, sterile and dry; the container should be labeled to record the name, abstinence time and time of semen collection. 5. The semen specimen should be insulated in winter, placed in a snug-fitting underwear bag, not tilted or inverted, and delivered to the laboratory within half to one hour if possible. It is recommended that it is best to take the semen in the sperm collection room of the hospital to facilitate the delivery of semen and reduce the factors affecting semen analysis.