The utility model relates to a vacuum destructor, include: a main bod. The setting is at the inside first appearance water cavity body of main part, the setting is in main part upper portion and with the atmosphere passageway that the first appearance water cavity body is linked together, the setting the main part lower part and with first and the 2nd inhalant canal that the first appearance water cavity body is linked together, the setting the main part lower part and with the receipt that is used for that first appearance water cavity was personally experienced sth. Part of the body and is linked together the first exhalant canal of first and the 2nd inhalant canal's rivers, it prevents return flow device and second activity and prevents return flow device to set up the first activity that possesses interlock function in first and the 2nd inhalant canal respectively. The utility model discloses circulating in the water route both provided two water route switching -over and the interlock function that advance, prevented the siphon protection simultaneously again when separately. The structure is succinct, and it needs multichannel water supply to prevent in the water utensil system of siphon protection to be applicable to.