The indices of oil／gas geochemical exploration are relatively independent of each other but atthe same time they show certain genetic relation．These indices have different functions for pre—dicting subsurface oil／gas potential．This paper proposed a method with which the’indexes can bestatistically classified and optimized，and synthesized information can be superimposed．By usingth e method in Optimizing geochemical exploration indices in a certain area of eastern China。infor．mation superimposition will yield good results．