Low temperature epitaxy of wurtzite ZnO and cubic MgZnO films is achieved on Si(111) by reactive electron beam evaporation. Mg content in MgZnO film is measured by X ray photoelectron spectroscopy and is larger than that in the evaporation source. Ultraviolet photoluminescence (UVPL) measurements show the emission peak of ZnO is at 393nm, while the peak of MaZnO is at 373nm. It is found that the UVPL peak of ZnO film grown under no O 2 environment is red shifted compared with that of ZnO film grown in the reaction chamber with additional O 2.