Abstract: The development of groundwater vulne rability concept is such a continu ously enriched,perfected and developed course which is from simple to complex,from considering inner factors merely to considering inner and outer factors comprehensively,and from divergence to agreement.Correspondingly,the assessment methods are from qualitative description by using maps to quantitative express by using mathematical model.The existing problems of groundwa ter vulnerabi lity assessment are put forward,and the present situation of research is discussed,and it points out that it is a hopeful research direction to assess the groundwater vulnerability by using the gray system theory,the fuzzy mathematical theory,the AHP method and the GIS techniques at last.