Antibacterial activity and uniform dispersion of zinc oxide(ZnO) had been studied and applied widely. But the property of ZnO was involved with particle size.The aim of this study was to further investigate morphology of ZnO prepared by sol-gel technology at different pondus hydrogenii(pH) value. By XRD analysis, ZnO particles were high purity under different pH value. In addition, the particles size of ZnO were minimum and uniform dispersion when the pH valeu was 8.5, and the mass ratio of polyethylene glycol(PEG) and zinc acetate was 1:2 by TEM analysis.