1, infertility patients should first ask a detailed and complete medical history 1, there is no congenital genetic disease, parents’ reproductive history and siblings’ reproductive situation. 2, whether there is delayed puberty or precocious puberty. 3, whether there is ejaculation disorder or erectile dysfunction, whether there is high temperature environment and exposure to rays. 2, physical examination 1, general examination such as the distribution of body hair, body shape and appearance, with or without breast development. Liu Qingyao of Beijing Fangshan Hospital of Traditional Chinese Medicine (BFTC) 2, genital examination includes the distribution of pubic hair, the penis with or without deformity, length and size, with or without circumcision, the size of testicles and epididymis, the texture, with or without swelling, as well as the vas deferens with or without defects, varicose veins of the spermatic cord. 3, commonly used auxiliary examination 1, semen routine to understand the density of sperm vitality and morphology. 2, sex hormone to understand the hypothalamus – pituitary – gonadal axis has no abnormalities. 3.Urological ultrasound To understand the size and blood flow of testicles, the presence of vas deferens and any abnormalities in the urinary system. 4.Transrectal ultrasound of seminal vesicle glands, ejaculatory ducts, vas deferens and prostate gland should be examined when obstructive azoospermia or dysplasia is suspected. 5.Cranial MRI Except for pituitary gland occupation or hypoplasia. 6, Karyotype and Y chromosome microdeletion To clarify whether azoospermia, severe oligozoospermia and congenital developmental abnormality are caused by chromosomal abnormality. 7, Testicular puncture or microscopic sperm extraction To clarify the development of testis and whether there is sperm production.