he preparation of multi-layer composition gradient hard thin films on titanium aluminide was realized with a renovated arc ion plating equipment where pure titanium and aluminum separated targets had been applied.Basing on the exploration of optimum technological condition for film deposition,the performance of high temperature oxidation resistance was measured and compared with the bland sample.It is found that the composition gradient thin films could be synthesized with high deposition speed up to 80 nm per minute,wide regulating range of alloying elements with great facilities like TiAl2 and TiAl3,while the high temperature oxidation resistance of titanium aluminide could be improved enormously after film depositions,less than 3 mg/cm2 in mass change after heating at 800 ℃ for 200 minutes.