Abstract: Birth defect is one of the main causes of the death of perinatal infant，and it is also supposed to be the major cause that leads to stillbirth，deadbirth and affect the growth of neonatals. It relates to environment factors，genetic factors，or the interaction of each other. For recent years，more and more researches have focused on the environment risk factors leading to birth defects. It was found that，birth defects were related to harmful physical or chemical factors(such as radiation,hyperthermia，lead，cadmium，zinc and folic acid)，maternal active and passive smoking， exposure to organic solvents and environmental pollution or exposure to agricultural toxic，drinking water disinfection by-products and so on. This paper aims to investigate the relationship between environment and birth defects，to provide a theoretical basis for reducing birth defects.

Key words: Congenital abnormalities, Environmental pollution, Toxic actions, Infant, newborn, Risk factors