PROBLEM TO BE SOLVED: To provide an ozone disinfection apparatus capable of conducting disinfection treatment for a short period of time, and to provide a disinfection method of the same.SOLUTION: In an endoscope disinfection apparatus 100 which disinfects an endoscope 10 that is arranged in a disinfection tank 2 and an object to be disinfected, by using ozone water, and discharges drainage water through a drain pipe 70, the endoscope disinfection apparatus 100 has an ozonolysis device 73 provided at the drain pipe 70, and discharges the ozone water after the disinfection treatment through the ozonolysis device 73. In addition, the endoscope disinfection apparatus 100 determines ozonolysis efficiency of the ozonolysis device 73 from a discharge period of time of the ozone water.目的在提供可在短時間進行殺菌處理的臭氧殺菌裝置及其殺菌方法。本發明係一種臭氧殺菌裝置,其係將作為殺菌對象物的內視鏡(10)以臭氧水進行殺菌處理的臭氧殺菌裝置(100),其具備有:殺菌槽(2),其係將前述內視鏡(10)浸漬在前述臭氧水;排出管(70),其係在前述殺菌槽(2)中將前述內視鏡(10)浸漬在前述臭氧水後,將該浸漬後的臭氧水作為排水來進行排出;及臭氧分解器(73),其係被配置在前述排出管(70),通過前述浸漬後的臭氧水來將該臭氧水中的臭氧進行分解處理。1a‧‧‧前板1b‧‧‧側板6‧‧‧供水口12‧‧‧排水口13‧‧‧腳輪41‧‧‧氧供給口70‧‧‧排水管71‧‧‧第一排水管72‧‧‧第二排水管73‧‧‧臭氧分解器100‧‧‧內視鏡殺菌裝置(臭氧殺菌裝置)