Objective To investigate the differentially expressed endogenous metabolites and metabolic pathways in the brown adipose tissue（BAT） of plateau pikas at different altitudes based on ultra-performance liquid chromatography-quadruple time-of-flight mass spectrometry（UHPLC-QTOF-MS），as well as the metabolic molecular mechanism for BAT to adapt to extreme high-altitude environments. Methods Eight pikas captured from Guoluo area（4 360 m） of Qinghai Province in China were established as MD group，and eight pikas captured from Menyuan area（2 900 m） of Haibei Prefecture were established as MY group. UHPLC-QTOF-MS was used to analyze the metabolites in BAT samples of the two groups，and Simca software was used to perform the principal component analysis （PCA） and the orthogonal partial least squares-discriminant analysis（OPLS-DA） of the metabolic profile features of BAT. The t-test，volcanic map analysis，and KEGG metabolic pathway analysis were performed for differentially expressed metabolites，and a bubble map was constructed. Results PCA and OPLS-DA showed that the BAT metabolomics in both groups showed significant clustering distribution，and these metabolites were involved in various life activities such as glucose metabolism，lipid metabolism，amino acid metabolism，nucleotide metabolism，and bile acid metabolism in the body. Among these metabolites，glucose 6-phosphate，cholic acid，ADP ribose，adenosine，deoxycytidine，and L-phenylalanine were significantly upregulated in the BAT of the MD group（P<0.05），while norepinephrine，stearic acid，urea，ornithine，and propylthiouracil were significantly downregulated（P<0.05）. The pathway enrichment analysis showed that BAT metabolism was associated with the metabolic pathways of phenylalanine，phosphopentose，tyrosine，and tryptophan. Conclusion Extreme high-altitude environment effectively activates non-shivering heat production in BAT by affecting the energy-related metabolic pathways in the body，promotes adipose tissue differentiation and white adipose browning，and increases the proportion of BAT，thereby helping to adapt to the extreme high-altitude environment.