Abstract: It is very important to study the risk assessment of groundwater pollution in the decision of the project. However, the result of the groundwater pollution risk assessment has uncertainty because of the uncertainty of the groundwater system itself. The uncertainty exists in the progress of groundwater pollution risk assessment, and it is necessary to analyze the uncertainty during the groundwater pollution risk assessment. In general, the result of groundwater pollution risk assessment based on uncertainty is more practical and valuable compared with the determinate groundwater system. This paper illustrates the classification of uncertainty (stochastic and fuzzy uncertainty) in the groundwater pollution risk assessment, summarizes the methods of uncertainty analysis (stochastic theory method, fuzzy theory method, integrated fuzzystochastic method and other methods) in the field of groundwater pollution risk assessment at home and abroad. In the end, the development of the theory of uncertainty in the future research of groundwater pollution risk assessment is also based on the current research situation of all the methods.