Abstract: It is difficult to determine water resources from multiple aquifers in a new area when the water sample amount is small.If the resources are mixed together by mine flood,the problem become more difficult.However,coal mines need quick,accurate and effective methods to discriminate the water resources.By taking advantage of the features of the discrimination between two resources that still has a better result even if the sample amount is small,the discriminants are established.Discriminated pair by pair,mine flow resources are determined according to their highest possibility.The method was successfully applied to Renlou Coal Mine to discriminate mine flow resource that was hard to determined by experience.The effect of grouting was confirmed and the proposal about the waterproof door was canceled.The conclusion is proven to be corrcet by production.This method can be broadly used in the area where the sample amount is small.