The invention relates to a method for detecting multiple anions in water by using an indicator displacement colorimetric sensor array. The method comprises the following steps of: mixing several colored metal ion chelating agents and metal ion receptors which correspond to the colored metal ion chelating agents under the condition of an aqueous solution to obtain a chelate, so that the indicator displacement colorimetric sensor array is constructed; and displacing metal ions from the colored chelate by means of the precipitation reaction between different anions and metal ions and the effect of the further generation of complexes, so that the change of the color of the chelate is caused. By the method, whether ten kinds of trace amount of anions, namely S<2->, F<->, Cl<->, Br<->, I<->, SO4<2->, PO4<3->, CrO4<2->, NO2<-> and C2O4<2-> in water exceed the national discharge standard of sewage or drinking water can be rapidly determined. In the testing process of a sample, an atlas of the sample is compared with a ''fingerprint atlas'' by mathematical statistics methods such as cluster analysis and principal component analysis, so that an unknown anion is subjected to qualitative or semiquantitative analysis.