Abstract: Homemade experimental apparatus is adopted to simulate the CO_2 corrosion of all kinds of steels at plug flow.The effects of different steels on CO_2 corrosion are studied by analyzing the coupon surface morphology,corrosion rate through electronic microscope and corrosion coupon.The results show that the resistance to uniform corrosion of 304 stainless steel is obviously higher than those of A333,X65 and X70steel;the resistance to uniform corrosion of stainless steel 304 changes little in a wide range of corrosion conditions;the corrosion rate appears larger fluctuation along with the change of corrosion conditions of A333,X65 and X70;there is a little difference in the uniform corrosion rate among the steel types of A333,X65 and X70.