The effects of (NH4)2Sx treatment on the surface electronic properties of the thin indium tin oxide (ITO)-doped ZnO films have been examined in this study. According to the experimental results, we found that the formation of S-metal bonds and the removal of oxygen vacancies near the (NH4)2Sx-treated ITO-doped ZnO surface could lead to an increase in the surface energy and the work function, meaning that (NH4)2Sx treatment might be more helpful to form the uniform deposition of the organic semiconductor on ITO-doped ZnO surfaces and improve the efficiency of ZnO-based organic devices.