Abstract: 【Objective】This study aimed to investigate the response characteristics of liver metabolism of Gymnocypris przewalskii under salt stress， so as to provide theoretical basis for enhancing environmental adaptability of Gymnocypris przewalskii after artificial proliferation and release and improving resource contribution rate.【Method】Untargeted liquid chromatography-tandem mass spectrometry （LC-MS/MS） was employed to profile the liver metabolomic changes in juvenile Gymnocypris przewalskii exposed to different salinity （10‰， 15‰， and 20‰）， with individuals under 5‰ salinity stress as control group. Multivariate statistical methods were applied to screen differential metabolites and identify key metabolic pathways.【Result】The survival rate statistics showed that juvenile Gymnocypris przewalskii maintained a survival rate ≥ 96% within 48 h of 5‰， 10‰， and 15‰ salinity stresses， exhibiting robust tolerance， whereas all individuals died within 48 h of 20‰ salinity stress， suggesting that this salinity exceeded their tolerance limit. Principal component analysis （PCA） revealed that a clear separation in metabolic profiles between each salinity stress group and control group， with the separation degree of samples at the first and the second principal components intensifying as salinity increased. Within the tolerable salinity range （10‰-15‰）， the metabolic pathways included biosynthesis of unsaturated fatty acids， glyoxylate and dicarboxylate metabolism， glycerophospholipid metabolism， choline metabolism in cancer， pyruvate metabolism， vitamin B6 metabolism， propanoate metabolism， and arginine and proline metabolism in liver of Gymnocypris przewalskii were significantly enriched （P<0.05， same below）. Under 20‰ salinity stress， the pathways included protein digestion and absorption， aminoacyl-tRNA biosynthesis， central carbon metabolism in cancer， biotin metabolism， carbon metabolism， pyruvate metabolism， and nicotinate and nicotinamide metabolism significantly enriched.【Conclusion】Gymnocypris przewalskii exhibits a clear metabolic threshold dependence in response to salt stress. Within the tolerable salinity， the organism primarily employs active regulation to maintain homeostasis through remode-ling lipid， energy， and amino acid metabolism； once the threshold is exceeded， the organism is forced to activate glutathione-centered antioxidant defense， accompanied by concurrent purine metabolic disturbances. Under extreme stress， Gymnocypris przewalskii faces a metabolic trade-off dilemma between “homeostasis maintenance and stress defense”.