Effect of Si-content on the oxidation of three Fe-Si-C alloys containing 1Si, 3Si and 6Si was studied in dry air at 600~1000℃. The oxidation kinetics generally revealed complex and irregular in all cases, although the overall weight-gain data increased with increasing temperature. It was found that the 6Si-alloy exhibits the superior oxidation-resistance, as compared to the lower Si-content alloys. The scales formed on all alloys were composed of mostly Fe2O3/Fe3O4, while minor amounts of Fe2SiO4-or SiO2-enriched zone were observed in the scale/substrate interface.