Zn0.99Cu0.01O films were studied experimentally and theoretically.The films were prepared by pulsed-laser deposi tion on Pt(111)/Ti/SiO2/Si substrates under various oxygen pressures to investigate the growth-dependence of the ferromag netic properties.The structural,magnetic,and optical properties were studied,and it was found that all the samples possess a typical wurtzite structure,and that the films exhibit room-temperature ferromagnetism.The sample deposited at 600℃and an oxygen pressure of 10 Pa showed a large saturation magnetization of 0.83μB/Cu.The enhanced ferromagnetism in the(Cu,Li)-codoped ZnO is attributable to the existence of Zn vacancies(VZn),as shown by first-principles calcu lations.The photoluminescence analysis demonstrated the existence of V Zn in both Zn0.99Cu0.01O and(Cu,Li)-codoped ZnO thin films,and this plays an important role in the increase of ferromagnetism,according to the results of first-principles calculations. Zn0.99Cu0.01O films were studied experimentally and theoretically. The films were prepared by pulsed-laser depostion on Pt (111) / Ti / SiO2 / Si substrates under various oxygen pressures to investigate the growth-dependence of the ferromag netic properties. The structural, magnetic, and optical properties were studied, and it was found that all the samples have a typical wurtzite structure, and that the film exhibit room-temperature ferromagnetism. The sample deposited at 600 ° C and an oxygen pressure of 10 Pa showed a large saturation magnetization of 0.83 μB / Cu. The enhanced ferromagnetism in the (Cu, Li) -codoped ZnO is attributable to the existence of Zn vacancies (VZn), as shown by first-principles calcu lations. The photoluminescence analysis demonstrated the existence of V Zn in both Zn0.99Cu0.01O and (Cu, Li) -codoped ZnO thin films, and this plays an important role in the increase of ferromagnetism, according to the results of first-principles calculations.