Influences of temperature on CO2 corrosion behaviors of P110 steel were studied in stimulated oilfield environments. Morphologies of scales and their effects on corrosion rate and corrosion shape were analyzed by SEM and XRD. The results showed, at 40℃, corrosion products were similar to loosen soil, few and hanging on the surface of the material composed by deposited KCl. In 90℃, corrosion products were grains, compact and much holes in it, constituted by calcium/magnesium/iron carbonate and few KCl and Fe2O3. In 140℃, corrosion products were in the similar morphology as compact clay in the outer layer and grains in the inner layer, made up of FeCO3 and KCl. The phenomena of different morphology in different temperature resulted in that the maximal corrosion rate presented in 90℃.