Abstract: Objective: To evaluate the regulating effect of black jerusalem artichoke oligosaccharide on the blood lipid level in hyperlipidemic mice and give a preliminary investigation to the mechanism of lowering blood lipid. Methods: According to the evaluation method of auxiliary hypolipidemic function in the national standard, C57BL/6 mice were fed with high-fat diet to establish a mixed hyperlipidemia animal model. The model animals were randomly divided into MC group (MC), active control group (AC), black jerusalem artichoke oligosaccharide low, medium and high dose groups (OSL, OSM, OSH). At the same time, a blank control group (CK) was set up. There were eight mice in each group, and the dose of gavage was 0.2 mL/d for each mouse. Gavage had lasted for 46 days. CK group and MC group were given normal saline, AC group was given 1.0 mg/(kg·bw) atorvastatin, and black jerusalem artichoke oligosaccharide groups were given 0.25, 1.25, 2.50 g/(kg.bw) black jerusalem artichoke oligosaccharide solution respectively. The blood lipid level and the contents of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA) in serum were detected. The morphological changes of mouse liver were observed. The expression of sterol regulatory element binding protein-1c (SREBP-1c) and peroxisome proliferator activated receptor-γ (PPAR-γ) in mouse liver were detected. Results: The triglyceride (TG), total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C) in the MC group were significantly higher than those in the CK (P<0.01), and the high density lipoprotein cholesterol (HDL-C) were significantly lower than those in the CK (P<0.01), indicating that the mixed hyperlipidemia was successfully modeled. The levels of HDL-C in the medium and high dose groups of black jerusalem artichoke oligosaccharide were significantly higher than those in the MC group (P<0.01 or P<0.05), the levels of TG and LDL-C were significantly lower than those in the MC group (P<0.05), the levels of SOD and GSH-Px were significantly increased (P<0.01), the level of MDA was significantly reduced (P<0.01), and the expression of SREBP-1c was significantly decreased (P<0.01). The fatty changes of mouse liver were alleviated to a certain degree. Conclusion: The black jerusalem artichoke oligosaccharide could improve the blood lipid level of hyperlipidemic mice, and the lipid-lowering mechanism was closely related to the antioxidant stress and the inhibition of SREBP-1c expression.