The pulse vacuum autoclave extracts vacuum and fills steam into the sterilization room for many times to make the sterilization chamber reach a certain vacuum degree, and then fills saturated steam to reach the set pressure and temperature, so as to achieve the purpose of sterilization of the sterilized substance. It is suitable for the sterilization of solid instruments, type-A hollow-cavity instruments, implantable instruments, dressing fabrics, rubber catheters, non-sealed liquid items, etc.