In order to detect the partial discharge with the metallic particle in GIS the AE(Acoustic Emission) sensor was designed and simulated by ANSYS 5.5 and manufactured as the coupled vibration mode. The measured resonant frequency and the maximum sensitivity frequency of three coupled AE sensors were as follows ; 147.88 kHz in 8.1mm $Phi$$ imes$8.1mm 128.82 kHz and 58.8 kHz in 9.5 mm$Phi$$ imes$9.5mm, 85.22 kHz and 32.6 kHz in 14.3 mm$Phi$$ imes$14.3 mm, resonant frequency of the AE sensor. The AE sensor of 9.5 mm$Phi$$ imes$9.5mm responded higher than the other coupled vibration mode AE sensor at the partial discharge detection in GIS.