Abstract: Groundwater quality evaluation is a problem with multi-factor classification and discrimination.This paper proposed a method of support vector machine used in water quality evaluation.This method is based on an idea of decision two-prong tree.The model of water environment quality evaluation based on support vector machine is established.The evaluation model is used to evaluate the shallow groundwater quality in Huainan with 75 water samples,and is compared with the fuzzy comprehensive evaluation method.The results are essentially in agreement with the fuzzy comprehensive evaluation method.The model is of lots of virtues such as less samples demanded,modeling convenience and universality as well as good practical value.