A mixed sterilization apparatus using hydrogen peroxide and ozone, comprising: a sterilization chamber (2) which holds a sterilization subject and is sealed from outside an ozone provider (3) which converts an oxygen-containing substance outside the sterilization chamber (2) or oxygen contained inside the sterilization chamber (2) and provides the converted ozone into the sterilization chamber (2) a vacuumization accelerator (4) which vacuumizes the inside of the sterilization chamber (2) and a hydrogen peroxide vaporizer (51) which vaporizes hydrogen peroxide and provides it into the sterilization chamber (2), wherein the vacuumization accelerator (4) comprises: an ozone decomposer (7) which decomposes the ozone inside the sterilization chamber (2) and a hydrogen peroxide decomposer (6) which decomposes the hydrogen peroxide inside the sterilization chamber (2).
