Objective:To explore whether chronic low-dose polychlorinated biphenyl 118(PCB118)could induce nonalcoholic fatty liver disease(NAFLD)in rats. Methods:Wistar rats were randomly divided into 4 groups and injected intraperitoneally with PCB118[10,100 or 1 000 μg/(kg·d)]or corn oil[0.5 mL/(kg·d)]for 13 weeks,respectively. Serum levels of alanine transaminase(ALT),aspartate aminotransferase(AST),glucose(GLU),triglyceride(TG),total Cholesterol(TC),low-density lipoproteincholesterol(LDL-c),high-density lipoprotein cholesterol(HDL-c)were measured,and the mRNA expresion of interleukin-1β(IL-1β),tumor necrosis factor-α(TNF-α)and fibrogenic factor transforming growth factor-β1(TGF-β1),matrix metalloproteinase-2(MMP-2),α-smooth muscle actin(α-SMA)were quantified. Hepaticsteatosis,inflammatory cell infiltration and liver fibrosis were observed by HE staining and Sirius red staining,respectively. Results:Compared to control group,after stimulation with different concentrations of PCB118,serum ALT,TG,TC,GLU,LDL-C,HDL-C levels were significantly increased(P < 0.01),and serum AST level was slightly increased,but no statistical significance was observed(P > 0.05). The mRNA expression levels of IL-1β,TNF-α,TGF-β1,MMP-2 and α-SMA increased,and were significantly different compared with the control group(P < 0.05). HE staining showed steatosis and inflammation in the liver of rats in PCB118-treated group was more serious than that in the control group,and Sirius red staining showed that the hepatic lobule structure was disordered with obvious red staining area in PCB118 treatment group. Conclusion:Chronic low-concentration PCB118 could promote liver fibrosis through inflammatory mechanisms and induce NAFLD in rats.