The work aims to improve the high temperature oxidation resistance of TiAl alloy. An Al-SiO2 composite coating was prepared on the surface of TiAl alloy by slurry and electrodeposition. The high temperature oxidation resistance of the coated TiAl alloy was evaluated by static air oxidation test. The phase composition of the coating before and after high temperature oxidation was analyzed by X-ray diffractometer. The surface morphologies and cross-sectional microstructure of the samples were analyzed by scanning electron microscopy. After oxidation at 1000 ℃, the aluminide coated TiAl alloy exhibited good oxidation resistance and the weight gain for 100 h was 10.44 mg/cm2. However, a yellowish oxide layer consisting of TiO2 was detected on the surface, and some defects such as cracks were observed. Moreover, serious interdiffusion of elements occurred between the coating and substrate during the heating treatment process. The surface morphology of the Al-SiO2 composite coating almost kept unchanged after oxidation for 100 h, and no obvious defects were observed. The oxidation resistance of the specimens increased with the prolonging of electrodeposition time for SiO2 interlayer. The best resistance was observed when the SiO2 interlayer was electrodeposited at -2 mA/cm2 for 300 s, and the oxidation weight gain was only 3.03 mg/cm2. The Al-SiO2 composite coating can effectively improve the high temperature oxidation resistance of TiAl alloy.