Congo red is an organic dye used as a representative for organic contaminant of water; the prepared magnetic Nano particles is used in the removal of Congo red under many parameters including pH and the NixZnxFe2O4 concentrations. The results show that Congo red (CR) removal was succeeded using photo degradation method in the presence of NixZnxFe2O4 as a catalyst. It succeeded to eliminate about 97% of 40 ppm CR after 3h. Photo catalytic degradation of CR could be carried out successfully over a pH range form 6-10. The pH affects not only surface properties of NixZnxFe2O4 nanoparticles but also the dissociation of dye molecule and the formation of the hydroxyl radical.