Objective To evaluate the effects of telmisartan by SOCS-3/SREBP-1c pathway and its efficacy of improving insulin resistance (IR) in rats with high-fat diet-induced nonalcoholic steatohepatitis (NASH). Methods A total of 70 SD male rats were assigned randomly into 3 groups:A (normal control, 20 rats, basic diet), B (model control, 30 rats, high-fat diet) and C (treatment with telmisartan, 20 rats, high-fat diet). After the IR-NASH model was made successfully, proved by 10 rats randomly from the group B with euglycemic hyperinsulinemic clamp technique (EHCT) and liver histology, the rats in the group C were intragastrically administrated telmisartan (5 mg/kg/d) for 4 weeks, and then all rats were tested with EHCT and sacrificed to test the blood chemistry, interleukin-6, homeostasis model assessment of insulin resistance, hepatic pathological analysis, and semiquantitative RT-PCR for determining SOCS-3 and SREBP-1c mRNA. Results Rats with high-fat diet developed steatohepatitis and insulin resistance at the 12th week and had more weight gain and higher liver index at the 16th week. IL-6, SOCS-3 and SREBP-1c mRNA expressions in the group B were up-regulated obviously, and each was positively correlated with the velocities of glucose infusion rates at 60~120 min. Blood chemistry and pathological observation in the group C were all improved; both SOCS-3 and SREBP-1c mRNA were down-regulated, and each negatively correlated with VGIR60-120, while serum IL-6 stayed at a high level. Conclusions Telmisartan can remarkably improve hepatic function and insulin resistance in rats with IR-NASH, the mechanisms of which would not be by path of reducing the secretion of IL-6, but by down-regulating the expressions of SOCS-3 and SREBP-1c mRNA.