In this work we used the environmentally friendly method to prepared ZrO2 nanoparticles utilizing the extract of Thyms plant, the ZrO2 NPs was characterized by different techniques such as FTIR, ultraviolet visible, Atomic force microscope, Scanning Electron Microscopy, X-ray diffraction and Energy dispersive X-ray. The average crystalline size was calculated using the Debye Scherres equation in value 7.65nm. Atomic force microscope results showed the size values for ZrO2 NPs were 45.11nm, and there are several distortions due to the presence of some large sizes. Atomic force microscope results showed the typical size values for ZrO2 NPs were 45.11 nm, and there are several distortions due to the presence of some large sizes, the results of SEM show that values size of particles ZrO2 NPs was 18.70 nm, zirconium oxide nanoparticles are formed in small clusters. Antimicrobial activities have been studied of ZrO2 NPs against one type of positive bacteria such as Bacillus, Klebsiella and Candida fungus in different concentrations, ZrO2NPs showed different effectiveness against these different types of antimicrobials. ZrO2 NPs was studied to inhibit breast cancer cell line (MCF-7). The results showed a high ability of the ZrO2 NPs to inhibit cancer cells
