Testicular biopsy is an important test for male infertility. Through testicular biopsy observation, the spermatogenic function of the testes and the degree of spermatogenic disorders, as well as the ability of the testes to synthesize steroid hormones, can be directly estimated. Valuation of fertility and can provide visual information, and is an important basis for treatment selection and prognosis. Testicular biopsy can reveal the following pathological changes: (1) Normal testicular structure: prepubertal varicocele is small, without basement membrane, with only primitive germ cells and supporting cells, and inconspicuous interstitial cells. Post-pubertal varicocele can be seen as intra-tubular spermatogenic epithelium, spermatogenic cells at all levels (spermatogonia, spermatocytes, spermatocytes) and supporting cells, with many spermatozoa on the luminal surface of the tube, and normal varicocele boundary membrane and interstitium. The reproductive pathological changes of the testis were mainly found in the spermatogenic epithelium of the varicocele and the basement membrane of the varicocele. (2) Hypospermatogenesis: spermatogenesis is present, but the spermatogenic epithelium is thinned and the number of spermatogenic cells at all levels is reduced. (3) Spermatogenic arrest: spermatogenesis is stagnant at a certain cell stage and cannot form spermatozoa, mostly seen in the spermatocyte stage, followed by the spermatocyte stage, and less often in the spermatogonia stage. (4) Spermatogenic cell shedding and disorder of arrangement: immature spermatogenic cells, spermatocytes and sperm cells are shed in clumps in the lumen of the varicocele, blocking the lumen and not discharged. This is often accompanied by disorder of spermatogonia arrangement. (5) Supporting cells only syndrome: Only supporting cells are present in the varicocele, but there is no spermatogenic cells. The duct diameter is reduced, the boundary membrane is thickened, and the interstitium is hyperplastic. This is a congenital anomaly with no spermatozoa and no fertility, but normal secondary sexual characteristics. (6) Mixed lesions: multiple abnormalities are seen in the varicocele, such as various types and degrees of spermatogenic disorders: spermatogenic arrest, abscission disorders; mixed presence of boundary membrane hyperplasia or hyaline-like degeneration. (7) Immature testes: In adults, the developmental state of the testes still stops before puberty, the diameter of the varicocele is small, the lumen has not yet appeared, and there is no spermatogenesis. (8) Hyaline degeneration of the varicocele: the development is rapid and progressive, manifested as thickening of the boundary membrane of the varicocele, hyaline-like degeneration, and expansion to the lumen and interstitium, resulting in increasing shrinkage of the lumen, accompanied by different degrees of spermatogenesis. In severe cases, all kinds of cells in the tubules disappeared, and only the crumpled shadow of the varicocele remained.