Geochemical primary halo exploration indexes for metallic ore deposits include single element index, multielement index and combinational index. The study and application of these indexes are carried out mainly in such fields as the judgment of the erosion section of an ore body, the evaluation of blind ore body and the recognition of dispersed mineralization. With the ending of the surface ore exploration, the oreprospecting work has laid emphasis on looking for blind ore bodies in the depth. On the basis of past work, the depth and range of index application should be raised. With the improvement of analytical technique, the strengthening and development of elements not analyzed in the past as well as the study of the indication role of isotopes and modes of occurrence of elements should be emphasized so as to realize quantfication of anomaly indexes, put forward new indexes and eventually improve the oreprospecting effect of primary halo.