The groundwater quality is a very complicated synthes is that has obvious randomness and fuzzy character. The groundwater vulnerability evaluation is an issue of typical qualitative and quantitative analyses. The conventional DRASTIC index method is only suitable for the essential vulnerability evaluation but can not reflect the special vulnerability. Owing to applying the adding - weight evaluation method, the influence of the continuous changes in index values of evaluation factors on the groundwater environmental vulnerability is concealed. This paper discusses the methods of the ground water environmental vulnerability evaluation and applies the fuzzy theory and the neural network theory to the evaluation and establishes an AHP - based fuzzy comprehensive evaluation model and a neural network model which are validated by the application in Ningling county. At last, the three methods are analyzed comparatively. 