Abstract: The problem of birth defects has becoming one of the most important issues in public health research fields. Risk factors of birth defects include genetic, environmental and gene?－environment interactions. Except the independent genetic factors, which accounts a little part of the whole，all other most risk factors are preventable, commonly related with environment and have geo?－spatial characteristics. With the fast development of information technologies, theories and methods from geo?－science have been applied into many research disciplines with Geographical Information System（GIS） as the foundation. This paper has introduced the process of geo－science applications into the birth defects analysis, includes the survey, monitoring of birth defects cases， identification of the environmental risk factors and assessment of the intervention measures. The frame work of geo?－science analysis into birth defects study has been explained with international process on this issue, and the prospects and problems in the application have been discussed as well.

Key words: Birth defects, Disorders of environmental origin, Information science, Geo－science research