In this study, Tibetan sheep lived at three altitudes (4500 m, 3500 m, 2500 m) were used for proteomic and metabolomic studies of the skin and two altitudes (4500 m and 2500 m) were used for macro-genomic and metabolomic studies of the skin microbes, as well as joint multi-omics analyses, to gain insights into the extreme environments on the skin and the skin microbes and their metabolites.