Abstract: Surface treatment technology of extra-heavy oil and petroleum-associated gas corrosion reason were analyzed.Screening test of corrosion inhibitor was conducted.The effectiveness of several corrosion inhibitors was studied, and it was found that the effectiveness of three corrosion inhibitors supplied by different manufacturers was good.The corrosion inhibiting rates are 44.99%.37.40% and 39.45% respectively.The influence of corrosion inhibitor concentration, temperature and time on the corrosioninhibiting rate was separately evaluated.The results show that corrosion inhibiting rate was more than 55% when concentration of corrosion inhibitor was at 500 mg/kg, and the corrosion inhibiting rate decreased markedly when temperature was at 80℃.Corrosion inhibiting rate decreased slowly with the increase of corrosion reaction time.Corrosion inhibiting rate was stable when sorption-desorption process reached a balance state.The effectiveness of corrosion inhibitor formulated was researched, which the corrosion inhibiting rate was more than 90%.