Varicocele is one of the common causes of male infertility, and according to relevant statistics the incidence of varicocele with infertility is about 35% to 40%. Sperm quality is abnormal in 50% to 80% of patients with varicocele, and testicular biopsy reveals bilateral sperm disorders. The mechanism by which varicocele causes infertility is not completely understood to date, but it is generally believed that it may be related to the following mechanisms. (1) Elevated testicular temperature. The normal maintenance of the spermatogenic function of the testes depends on the maintenance of a suitable testicular temperature. In varicocele, the venous blood around the testis is depressed and the blood in the spermatic cord is refluxed, causing the higher temperature blood in the abdominal cavity to pour directly into the testis and causing the testicular temperature to be impaired, thus increasing the testicular temperature and causing the testicular spermatogenesis process to be impaired. ② Damage to the testis by vasoactive substances and toxic metabolites. The reverse flow of blood from the internal spermatic vein causes the endocrine products of the adrenal glands and kidneys, such as steroids and catecholamines, to enter the testes with the reverse flow of venous blood, affecting the production of testicular sperm. ③ Testicular and epididymal microcirculation disorders. According to the study, in the local area of testis, capillary and venous stasis and arterial blood flow decreases in patients with varicocele. This inevitably affects the function of the testes and epididymis. ④ The effect of varicocele on the function of the epididymis. Ultrastructural examination of the epididymis has been done with artificially induced varicocele in rats, and it was found that the epididymal tissue degenerates, the α-glucosidase activity in semen decreases, and the carnosine content decreases, indicating that the function of the epididymis is impaired. ⑤ Other causes, such as possible dysfunction of the male gonadal axis and disruption of the immune barrier, may be caused. In recent years, many scholars have also studied the mechanisms of varicocele infertility at the molecular level. In conclusion, the occurrence of varicocele infertility is the result of the combined effect of many pathways and factors. Does the infertility of varicocele necessarily require surgical treatment? First look at the following case.