The semen collection should be done 3-7 days after semen discharge, and smoking and alcohol should be prohibited, and drugs that have an effect on sperm production should be avoided. The best time to collect semen is in the morning, before collecting semen with warm water to wash hands, pubic area, especially the glans. Masturbation method or electric massage ejaculation method can be used to cause sperm discharge. The discharge of semen has a certain order, the first part comes from the prostate, epididymis and pot belly, accompanied by a large number of sperm, and the last part comes from the seminal vesicles, so the whole semen should be collected and no part should be missed, especially the first part. It is because the first part of the semen is easily lost that semen should not be collected by the in vitro ejaculation method. The container of semen should be clean, sterile and dry, and the temperature of the container before collection should be the same as the room temperature; the bottle should not be too large, but the mouth of the bottle should not be too small, so as not to shoot semen out of the bottle; it should also be labeled and recorded with the name and time of semen collection. On cold days, the semen specimen should be insulated and placed in a snug-fitting underwear bag, not tilted or inverted, and delivered to the laboratory within one hour if possible.