Abstract: Metabonomics techniques were used to investigate the mechanism and metabolic pathways of total extract of Amygdalus mongolicus against renal fibrosis in rats. Rats were randomly divided into a model group (MOD), a sham surgery group (SDG), a benazepril hydrochloride-treated group (BHT) and three groups treated with the total extract of Amygdalus mongolicus:low-dose group (TOT-L), middle-dose group (TOT-M) and high-dose group (TOT-H), with 10 rats in each group. The rats were given intragastric administration for 3 weeks and kidney and blood samples were taken. Pharmacodynamic studies and ultra performance liquid chromatography-quadrupole time of flight-mass spectrometry (UPLC-Q-TOF/MS) analysis were used to show that the total extract of Amygdalus mongolicus has an anti-fibrotic effect in rats. Compared with the MOD group, rats in the TOT-L, TOT-M and TOT-H groups showed a reversal in 67, 69, and 70 biomarkers, respectively, and shared 62 biomarkers. Reversal was observed for 7 key biomarkers related to renal fibrosis, including S-adenosy-L-methioninamine, ornithine, diketogulonic acid, and others, and changes in 5 metabolic pathways, including arginine and proline metabolism, pentose and glucuronate interconversions. These results give evidence of the metabolic pathways and the mechanism of action of Amygdalus mongolicus to prevent renal fibrosis in rats. The animal experiments were approved by the Medical Ethics Committee of Baotou Medical College (No. 20190314).