The threshold and different concentration levels of geochemical blocks of lead and zinc in Tuotuohe area were determined with geochemical methodology and technology and the blocks were delineated. The authors have summarized the spatial distribution characteristics of geochemical blocks and traced the possible of occurrence of large to superlarge deposits through a study of the internal structure of the geochemical blocks. It is pointed out that there are great potential to search for lead and zinc mineral resources in these geochemical blocks.