With the increasing pressure of social life, the worsening of environmental pollution, the psychological pressure caused by competition and other factors, the incidence of male infertility has been increasing year by year, and the patients tend to be younger and younger. Among them, azoospermia is one of the causes of male infertility, and its incidence rate is about 1%~2%, accounting for about 10%~15% of male infertility. What tests are needed to diagnose azoospermia? 1, semen examination Men take semen examination, after centrifugation and precipitation under the microscope to see whether there are sperms or not. Semen examination is the simplest, most convenient and fastest examination, and it is also an essential and important examination. 2.Endocrine hormone and inhibin B examination Measurement of endocrine hormones (FSH, LH, T, E2, etc.) can determine the spermatogenic function of testes, and make clear whether azoospermia is pituitary or hypothalamus, testicular, post-testicular, and other specific causes of azoospermia. Inhibin B is produced by testicular support cells, which can more directly reflect the spermatogenic function of testis than FSH, therefore, sex hormones combined with inhibin B can more accurately determine the spermatogenic function, which plays a crucial role in guiding the diagnosis and treatment of azoospermia. 3.Sperm plasma neutral a-glucosidase and fructose test is an important test to determine whether azoospermia is obstructed or not and the location of obstruction. 4.Chromosomal karyotype and Y chromosome microdeletion Chromosomal karyotype is used for the diagnosis of testicular dysplasia, external genital malformations and unexplained azoospermia, while Y chromosome microdeletion accounts for about 10% of the abnormalities in azoospermia, which is an indispensable and important test for the diagnosis of the etiology of azoospermia. 5, reproductive system ultrasound According to the reproductive system ultrasound, testicular size, epididymal development, epididymal ducts dilation and thickening and other issues can be found to determine the state of testicular spermatogenesis and epididymal obstruction, and the development of the seminal vesicle glands can be found to determine whether the vas deferens is underdeveloped or defective, and to further clarify whether there is distal testicular end of the obstructive azoospermia. 6.Sperm plasma free RNA test can predict spermatogenesis based on the detection of seminal plasma free RNA, which provides a better and non-invasive diagnostic method for the classification of azoospermia. 7. Testicular puncture or biopsy Testicular puncture or biopsy can differentiate obstructive azoospermia from non-obstructive azoospermia, and can also identify some potential lesions in the male testis. Multi-point biopsy pathology of the testis is still the gold standard for the diagnosis of azoospermia. In order to avoid passing on azoospermia to the next generation, patients must undergo genetic testing and counseling before undergoing assisted reproduction therapy.