OBJECTIVE：To study the improvement ef fects of sanggenone C on lipid accumulation in human liver cancer HepG2 cells induced by free fatty acid （FFA）. METHODS ：HepG2 cells were divided into control group ，model group ， fenofibrate group （10 μmol/L），sangerone C low ，medium and high concentration groups （2，4，8 μmol/L）. Except for control group，other groups were treated with 1 mmol/L FFA to induce lipid accumulation model ，and administration groups were cultured with relevant medium containing drugs. The lipid accumulation was observed by oil red O staining ，and lipid level and triglyceride （TG） content were also determined. Real-time PCR and Western blot assay were adopted to detect the mRNA and protein expression of PPARα，CPT-1，SREBP-1c，FAS，SIRT1 and PGC- 1α in HepG2 cells. RESULTS ：Compared with control group ， the nucleus was atrophied significantly and the volume became smaller ，and the number of lipid droplets was significantly increased；the level of lipid ，TG content ，mRNA and protein expression of SREBP- 1c and FAS were significantly increased （P＜ 0.05 or P＜0.01），mRNA and protein expression of PPARα，CPT-1，SIRT1 and PGC- 1α were decreased significantly（P＜0.01）. Compared with model group ，no obvious nucleus atrophy and normal volume were observed in sangerone C groups ，and the number of lipid droplets was significantly reduced ；the levels of lipid ，TG content ，mRNA and protein expression of PPARα pathway related genes （except for SREBP- 1c protein in saggenone C low concentration group ）were significantly reversed （P＜ 0.05 or P＜0.01）. CONCLUSIONS ：Sangenone C can significantly improve the lipid accumulation of HepG 2 cells，and its mechanism may associated with regulating PPAR α signaling pathway，improving cell lipid oxidation ability and inhibiting lipid synthesis.