Black scurf disease caused by Rhizoctonia solani, was a serious and common disease on potato worldwide. Effect of nanoparticles forms of Tri–calcium phosphate, copper oxide and silicon dioxide nanoparticle was evaluated at five concentrations to control black scurf disease in vitro and in vivo. Examination of treated R. solani with different tested nanoparticle was done using Transmission Electron Microscope (TEM). Activities of defense related enzyme were determined in artificially inoculated potato plants and tubers (cv. Spunta) with R solani.  Physical characteristics of tested nanoparticles exhibit that all of them are spherical in shape and varied in their sizes. Also, all tested nanoparticles exhibited inhibitory effect of R. solani. Non-copper oxide was the most effective one (56.42 %) in suppressing the mycelial growth of  R. solani at concentration 250 µl/L. The TEM examination of treated R. solani with different nanoparticles exhibit that instability they caused in cell wall thickness, abnormalities of nucleus and disappearance of nuclear membrane. All tested nanoparticles reduced of incidence and severity% of black scurf disease at concentrations 150 and 200 µl/L. during 2014 and 2015 seasons. Results cleared also that treating potato plants with different tested nanoparticles affected positively the activities of poly phenoloxidase, peroxidase, catalase and chitinase enzymes in leaves and tubers.