Abstract: Oceanic polymetallic nodules, as a kind of potential strategic resource, are getting more attention. The back-scatter intensity data from the Pacific Basins of the EM 122 multi-beam system on the Haiyang-6 vessel, have proven that the back-scatter intensity is related to certain degree with polymetallic nodules. Thus, it could be used a reference for the delineation of polymetallic nodule in the oceanic resource survey.