Nanophotocatalyst of TiO2/Zr obtained with Optimum trace amount of Zr, by employing the sol-gel method. Several spectroscopic techniques applied to characterize the structures and properties of nano photocatalyst. It founded that the effect of doping Zr ions to the TiO2 lattice led it to improve the surface properties and decreasing the particle size of nano photocatalyst. Therefore, it causes increasing specific surface area and photocatalytic activity as compared with pure TiO2. The photocatalytic activity of the nano photocatalyst employed for the degradation of Methyl parathion as organic waste in the aqueous solution under UV irradiation in a wooden batch reactor.