Azoospermia is one of the most troubling conditions among the male patients received in the fertility clinic. The causes of azoospermia can be broadly divided into three types: obstruction of the vas deferens, abnormal intercourse or ejaculation, and testicular spermatogenic dysfunction; for the first two cases, surgical repair or medication can be attempted, and pregnancy can also be achieved through “in vitro fertilization” (in vitro fertilization – single sperm injection), but for patients with testicular spermatogenic dysfunction, there is no definitive treatment except for some cases that can be improved through endocrine therapy. However, there is no definitive treatment for patients with testicular spermatogenic dysfunction, except for some cases that can be improved by endocrine therapy. For those patients with azoospermia due to spermatogenic dysfunction, testicular aspiration biopsy is routinely performed in the hope of finding a small amount of residual spermatogenic testicular tissue to extract sperm for “in vitro” fertilization; unfortunately, sperm cannot be found in more than half of these patients, especially those with testicular hypoplasia, severe atrophy, and associated genetic disorders. Unfortunately, sperm cannot be found in more than half of these patients, especially in those with testicular hypoplasia, severe atrophy, and associated genetic disorders. Therefore, many previous urological publications have listed testicular biopsy as a contraindication for patients with markedly reduced testicular volume (<5 ml), marked sex hormone abnormalities (FSH >32u/L or twice the upper limit of normal), Creutzfeldt-Jakob syndrome (47 XXY), and Kaman syndrome, suggesting that testicular tissue retrieval in these patients is of minimal significance and has little hope of finding sperm, and that sperm banks are recommended for donor insemination. In 1999, foreign scholars began to apply surgical microscopy to testicular excisional biopsy to increase the probability of obtaining sperm in patients with severe spermatogenic disorders; since then, more and more male physicians have used this technique to find sperm for their patients and successfully produce normal offspring, and, at present, the results of the procedure have been reported at home and abroad. The reported results of the procedure show that the success rate of surgical sperm retrieval does not decrease even if the patient has an abnormally small testicle size or a combined genetic disorder (Crohn’s disease), which gives hope to many patients who were previously sentenced to “death”. In a normal testis, there are hundreds of spermatogenic tubules that produce sperm that pass through the vas deferens and are finally discharged with the semen. However, in patients with severe spermatogenic dysfunction, only a few local spermatogenic tubules may remain, and the tiny amount of sperm produced in the vas deferens, after apoptosis, damage by various physical and chemical factors, and possible inflammation, often perish by the time they are ejected with semen, and even if there are occasionally left, it is like looking for a needle in a haystack to find them in several milliliters of semen. The principle of using microscope for testicular biopsy is to identify and extract the sperm from the source of microscopic sperm production, and after a series of separation and freezing, they can be used for subsequent “in vitro” fertilization.