The aim of this study was to explore the lipid-lowering effect of naringenin and the underlying mechanism in high-fat-diet-fed SD rats and 3T3-L1 cells. In this study, SD rats were divided into the normal chow diet group (NCD), high fat diet group (HFD), three treatment groups feeding high-fat diet with naringenin (100, 200, 400 mg/kg) for 12 weeks. Results indicated that naringenin treatment decreased total cholesterol (TC), triglyceride (TG) and the non-high-density lipoprotein cholesterol (non-HDL-C) levels in serum. Naringenin also alleviated hepatic steatosis and reduced the adipocyte size in the epididymis in high-fat-diet-induced SD rats. In addition, naringenin (25−75 µg/mL) decrease TG and TC levels in 3T3 mature adipocytes. The molecular mechanism of naringenin in the treatment of obesity were predicted by using network pharmacology. Real-time PCR analysis results showed that naringenin regulated the expression of lipid metabolism genes. Meanwhile, naringenin increased the AMPK (AMP-activated protein kinase) activity and the expression of AMPK phosphorylated protein in 3T3 mature adipocytes. And the inhibitory effect of naringenin on lipid accumulation in 3T3 adipocytes was abolished by Compound C. Molecular docking results indicated that naringenin could bind to AMPK protein. These results indicated naringenin reduced lipid accumulation through AMPK pathway.