Ozone is a strong oxidizing a gen, with a standard electrode potential of 2.07V.Oxidize materials, equipment a, surfaces wanted to clean. Ozone unfortunately, reacts with those materials and others leading to corrosion in those materials moreover those materials could lose their effectiveness. Because of multiple uses of Ozone, its effect on corrosion of Aluminum, Medium Carbon Steel, Copper & Brass in three different flow rates by weight losses method with benefits from linear fitting process was studied. The experimental shows that corrosion rates of Aluminum & Brass in three flow rates, decreasing with increasing the exposure time to corrosion, meanwhile the corrosion rates for Medium Carbon Steel & Copper decreasing only for (0.25 ft3/hr) and for another two flow rates (0.5 & 0.75 ft3/hr) the corrosion rates increasing with increasing the exposure time to corrosion, because of ozone gas flow rate positive& negative effected by forming oxide and hydroxide film which damage or not by increasing the corrosion intervals and ozone flow rates increasing. The average of total corrosion rates for the materials used in previous work increasing with increase the flow rate of Ozone in distilled water and the maximum value was (8.71×10-17MPY), meanwhile the minimum values was (4.08 ×10-17MPY).