ZnO films codoped with Ga and As were characterized in detail. It was observed by I–V measurement that the films maintain p-type characteristics even when the Ga/As ratio is as high as 9. Low-temperature photoluminescence spectra revealed emissions at 3.36, 3.35, 3.30, and 3.22 eV, which were assigned to the D°X, the A°X, the two-electron-satellite D°X, and the DAP transition, respectively. A PL peak also appeared at 3.34 eV in the case of Zn0.96Ga0.03As0.01O and Zn0.90Ga0.09As0.01O films. X-ray photoelectron spectroscopy indicated formation of Ga–As bonds with increasing Ga concentration, suggesting that the 3.34 eV peak is related to the Ga–As bonds.