ABSTRACT: Nanotechnology has noticeably developed with potential effects in every science specially by using nanoscale chemical element. Among nano material ZnO is more attention due to its special properties and its less hazard to environmental impact. ZnO like most of nanoparticles is toxic in organiams, however the toxicity of this nanoparticles can be used for antibacterial, antifungal, antiviral and antialga. To reduce the hazard effect of nanoparticles some manufact or chemical particles such as Nanoscale zero-valent iron are introduce that can be used for environmental remediation of polluted water, soil and sediments. In the present study, the effect of Nanoparticle ZnO on environment and different organisms from virous to fish has been reviewed and the application of nanoscale material in treatment of water are discuss