In recent years, the incidence of male infertility has been gradually rising, bringing pain to many families and putting heavy psychological pressure on many men. It is reported that about 15% of couples around the world are infertile, of which male infertility accounts for about 40% to 50%. In the last half century, due to the influence of environmental, psychological, social and other factors, the quantity and quality of male sperm have shown a significant decline in the trend of male reproductive health is under serious threat. Couples who have cohabited for more than one year without using contraception and the woman does not get pregnant due to male factors are called male infertility. Decline in sperm quality may pose an unguessable danger to the quality of human beings. For this reason, extensive research has been carried out on the factors affecting sperm quality, and it has been found that global environmental pollution is the main reason for the decline in sperm quality. Environmental factors affecting sperm quality include: 1. Metal elements: Metals that have been proven to be toxic to reproduction include mercury, lead and cadmium. Long-term exposure to these heavy metals can lead to a decline in the number of sperm, a decrease in sperm density, a decrease in sperm vitality, a decrease in the amount of sperm discharged at one time, and an increase in the proportion of malformed sperm. 2, pesticides and drugs: with the development of agriculture, the impact of pesticides on the quality of spermatozoa is more and more attention, such as dichlorvos, malathion, methylene blue, indocyanine, etc. can affect the sperm’s motility, so that the number of spermatozoa 8 less, the morphology of the change. 3.Organic substances: Many organic substances are toxic to sperm, such as benzene, formaldehyde, food additives and some other harmful chemicals will hinder the birth and vitality of sperm, and even lead to testicular atrophy. 4, gas (car exhaust): studies have found that the proportion of normal spermatozoa in people who often inhale car exhaust is significantly reduced. 5, radiation: germ cells are one of the most sensitive cells to radiation, excessive radiation on sperm can have adverse effects. Electromagnetic waves, nuclear radiation, X-ray irradiation are killers of human spermatozoa, which can make sperm cells abnormal, pregnant women miscarriage and fetal dysplasia. 6, temperature: high temperature will produce damage to the testicles, but exactly how high the temperature and how long the exposure time under this temperature will have an impact on the testicles, there is still a debate in the academic community. In animal experiments, fertility was reduced in males after being exposed to 38.5°C for 55 minutes. In real life, men should try to avoid staying too long in a high-temperature environment, such as sauna and hot water baths. 7, Drugs: Anti-cancer, hormone, antibiotic and other drugs can damage the function of male gonads, cause the decline of sperm quantity and quality, or lead to sexual dysfunction by affecting the endocrine function of the gonads. The effect of drugs on male fertility is affected by the type of drug, dosage, course of treatment, age of the patient and other factors. Generally speaking, the larger the dose of the drug, the longer the course of treatment, and the younger the age of the patient, the more serious the damage to fertility, and the longer the time needed to restore fertility. 8, mental tension to reduce sperm count: men with the acceleration of life and work, resulting in a number of men do not have time to exercise, so that the body’s resistance to decline, the quality of the body is getting worse and worse, especially men, the pressure of life, the long-term life of tension, and the body is in a state of emergency, in particular, it leads to a stress hormone affects the hypothalamus – pituitary – testicular gonadotropic axis, which can make the number of sperm obviously decline. Decrease in sperm count.