A PET bottle sterilization method for consecutively sterilizing multiple PET bottles (B) while conveying them, includes introducing hydrogen peroxide into a PET bottle (B) so as to sterilize its interior, and introducing hot air into the sterilized PET bottle (B) so as to eliminate hydrogen peroxide remaining inside it. This method includes introducing plasma into a PET bottle (B) by injecting plasma through a nozzle at at least one time point among a time point before hydrogen peroxide is introduced into the PET bottle (B), a time point after hydrogen peroxide was introduced into the PET bottle (B) and furthermore before hot air is introduced into the PET bottle (B), and a time point after hot air was introduced into the PET bottle (B).
