The effect of different concentrations of nickel (II) ions on the oxidation rate of mixed wastewater pollutants with ozone-air mixture for 30 minutes with an ozone concentration of 3 mg/l was studied. It was shown that adding nickel (II) ions at a concentration of 300 mg/l reaches the maximum degree purification of wastewater as a result of oxidative processes on the COD value, equal to 40.4%, which is 10.1% more compared to the catalytic oxidation of the investigated wastewater pollutants with the air oxygen participation.