An oxidizing gas pressurization system capable of supplying protective cooling water into an oxidizing gas pressurization unit such that the protective cooling water serves as a protective film against strong oxidizing power and cools the heat generated in the pressurization unit is disclosed. The oxidizing gas pressurization system for pressurizing and supplying an oxidizing gas such as ozone and chlorine includes an oxidizing gas storage unit, an oxidizing gas pressurization unit for pressurizing the oxidizing gas supplied from the oxidizing gas storage unit at a high pressure and discharging the oxidizing gas, and a cooling water supply unit for supplying protective cooling water serving as a protective film against the oxidizing pas supplied into the oxidizing gas pressurization unit.