Abstract: Acoustic agglomeration technology uses high-intensity acoustic field to make aerosol particles collide and condense rapidly, thereby, the mass concentration of particles is greatly reduced. Nowadays, once the underground cable fires, it will cause huge loss of life and property. The application of acoustic agglomeration technology can greatly improve the visibility of the fire scene and help people escape. In this paper, the experimental study of using the ultrasonic field to eliminate the smoke of the underground cable fire is studied. Firstly, an ultrasonic transducer of 18kHz is designed and its modal analysis is carried out. Then, a sound source prototype is made. The sound source test results show that the high-intensity ultrasonic transducer can emit the sound wave with a sound pressure level(SPL) up to 154.1 dB and 158.7 dB in the open space and in the agglomeration room, respectively. In open space, the higher the input power and the closer to the center of the disk, the higher the sound pressure level. The SPL at the middle monitoring point of the agglomeration room is the highest due to the reflection of the wall and bottom. The results of the agglomeration experiment show that when the SPL is 155 dB and the initial light transmittance is 8%, for liquidphase smoke and cable smoke, the light transmittance reaches 60% within 5 s and 15 s, respectively, which indicates that the agglomeration effect is significant under ultrasonic field and the agglomeration effect increases with the increase of the SPL.