A method for cleaning and sterilizing an object including a medical instrument, an animal medical instrument, a meat processing tool, and a cooking tool, wherein the target object is subjected to ultrasonic cleaning or stirring cleaning with alkaline electrolyzed water for a first predetermined time. After the alkaline electrolyzed water washing step, and after the alkaline electrolyzed water washing step, there is an acidic electrolyzed water washing step of stirring and immersing the object in acidic electrolyzed water for a second predetermined time.医療用器具、動物用医療器具、食肉加工用具及び調理用具を含む対象物の洗浄殺菌方法であって、前記対象物をアルカリ性電解水で、第１所定時間の間、超音波洗浄あるいは攪拌洗浄するアルカリ性電解水洗浄工程と、前記アルカリ性電解水洗浄工程の後、前記対象物を酸性電解水に、第２所定時間の間、撹拌洗浄あるいは浸漬する酸性電解水洗浄工程と、を有する。
