(1) Acting directly on the male gonads, affecting the function of spermatogenic cells of the testes that produce spermatozoa and Leydig cells of the testes; (2) Acting on the hypothalamus-pituitary-gonadal axis, affecting the normal secretion of hormones in the body, leading to changes in the levels of gonadotropins and testosterone, and ultimately affecting the fertility; (3) Impairing the ejaculation and erection functions of the penis, making it impossible for the semen to enter into the body of the spouse, leading to spermatozoal dysfunction; and (4) Negative impact on male libido and lack of normal sex life between couples. Drugs that affect male fertility include: (1) Immunosuppressants: the effect on fertility is related to the type of drug, dosage and time of use. These drugs include cyclophosphamide, vincristine, adriamycin, contramycin, azelnidazole, nitrogen mustard, procarbazide hydrochloride, cisplatin, and etoposide. Cyclophosphamide causes damage to male germ cells, often leading to irreversible reductions in fertility. Methotrexate has no significant effect on spermatogenesis, but may cause reversible infertility; discontinue 3 months before planned pregnancy. Leflunomide has little effect on male fertility, and due to lack of sufficient information, it is currently recommended that men taking leflunomide who also wish to have children may refer to the female patient regimen of anticholinergic amine 8 g 3/d for 11 d. Azathioprine, cyclosporine A, or mertilmicosporine do not appear to reduce fertility in men, but cyclosporine can cause a decrease in sperm density and viability. (2) Antihypertensive drugs: most of them mainly impair sexual function, such as certain diuretics can cause erectile dysfunction by lowering vascular resistance, leading to insufficient blood supply to the penis; the beta-blocker Xindean can affect libido and erectile function; andropause can affect fertility by affecting erectile function and libido and the potential impact on semen quality; and calcium channel blockers can inhibit the normal fertilization process. (3) Sex hormone drugs: anti-androgen drugs make the normal physiological function of androgens in the body affected (decreased libido and spermatogenic disorders), causing problems in fertility. More and more athletes abuse anabolic steroids, such as a large number of synthetic androgens can lead to hypogonadotropic hypogonadism, and normal gonadal function can be restored in most cases after stopping the drug. (4) Other drugs: some antimicrobial agents such as neomycin, erythromycin, gentamicin, etc. may cause a decrease in semen quality. Colchicine and allopurinol, which are used to treat gout, also have adverse effects on male fertility. Furacilin, cimetidine, salazosulfapyridine, cocaine, nicotine, and marijuana can impair spermatogenesis, but spermatogenesis and/or sperm function can return to normal after discontinuing the drug. Liuzosulfapyridine can affect late sperm maturation, and sperm quality can be restored to successful conception 2 to 3 months after discontinuation of the drug. Exposure to environmental toxins such as pesticides should also be noted.