The microstructure change and oxidation weight increase of Ti-48Al-2Nb-2Cr intermetallic compounds prepared by laser additive manufacturing at the temperature of 850 ℃ are studied, the difference of oxidation behavior between the as-deposited and the as-casted specimens is analyzed, and their oxidation mechanisms are disclosed. The results show that, when the oxidation time is same, the oxidation weight increase rate of the as-deposited specimen is obviously smaller than that of the as-casted specimen. After oxidation of 60 h, the oxidation layer of the as-casted specimen is completely delaminated from the alloy matrix, while the oxidation layer of the as-deposited specimen is well combined locally with the matrix. The compositions of oxidation films of the as-deposited and those of as-casted specimens are different, the former is TiO2/Al2O3/matrix and the latter is TiO2/Al2O3/TiO2+Al2O3/matrix.