Objective To prepare and evaluate a fluorine-containing corrosion inhibitor of high temperature acidification. Methods Corrosion inhibitor of high temperature acidification was prepared with fluorocarbon imidazoline quaternary ammonium salt as main component. The corrosion inhibitor performance of N80 steel was evaluated by weight loss method and electrochemical method in high temperature acidification condition. Thermostability and chemicalstability of fluorocarbon imidazoline quaternary ammonium salt were evaluated by TG/DTA and surface tension method. Results The result of weight loss evaluation showed that the corrosion rate was far below the level one standard of SYT 5405—1996 after corrosion inhibitor was added to N80 steel. In electrochemical test, polarization curve showed corrosion potential of electrode shifted positively, and the corrosion current was significantly lowered. EIS spectras showed the semicircle diameter of capacitance loop increased significantly, corresponding film resistance Rp was obviously magnified and suppressed the charge transfer of corrosion. Both electrochemical test and weight loss method proved the sound performance of the corrosion inhibitor in HCl solution, which was consistent with the result of weight loss method. The result of TG/DTA test showed fluorocarbon imidazoline quaternary ammonium salt started to be decomposed at 220 ℃, and completely decomposed at 400 ℃. The result of surface tension test showed the surface activity of fluorocarbon imidazoline quaternary ammonium salt was stable in 10%～25% HCl solution within 10 h. Conclusion The fluorine-containing corrosion inhibitor of high temperature acidification can effectively lower the corrosion of N80 steel in HCl at 90～140 ℃.