As an important means to adapt to the harsh working environment, wireless passive sensing technology still faces the difficulty that passive information can not cross the metal body in the application of burning-loss monitoring for aircraft heat-insulating layer. This paper proposes a new passive monitoring method based on the combination of acoustic energy coupling and circuit fusing. In this paper, the principle and implementation of the method are described, and the key principle of obtaining the status information of the embedded fuse in the heat-insulating layer across the metal medium is verified by experiments. The results show that the method can effectively penetrate the aluminum alloy bulkhead with typical thickness, and can effectively identify the change of the detection signal in the temperature range of 25 ℃–85 ℃. This method also has ability to avoid the impact of strong vibration environment and the drilling for metal body, and can be used for on-line health monitoring which faces to the heat-insulating layer of high-speed aircraft, reentry spacecraft and the new generation of space shuttle transportation system.