Abstract: Pattern of the calling song,stridulatory mechanism and the hearing sensitivity of bushcricket Deracantha onos(Orthoptera,Tettigoniidae) were studied by acoustical analyses and neurophysiological techniques.Bushcrickets use an elytro-elytral mechanism in sound production:the denticulated vein (file) on the undersurface of the left elytron is rubbed by the inside edge (plectrum) of the right elytron at a rate of 30-33/s.No change in the activity of the motor neurons controlling the movement of the elytra was found after removing some teeth of the file.The file-train of pulses is the elementary component of the calling song of D.onos.Each file-train is composed of one elytra-opening pulse and 11-13 elytra-closing tooth pulses.Each tooth rubbing of the file against the plectrum elicits a damping oscillation called "tooth pulse" .The rate of the tooth pulses is about 450/s.The power spectrum of the song covers a wide frequency band from 6 to 30kHz with a peak at 12-14 kHz.The song intensity is about 110 dB L_p at a distance of 10cm from the animal.The best hearing sensitivity is in the range of 12-15kHz with the lowest threshold of 35 dB L_p.The narrow-band filter characteristic of hearing shows that D.onos possesses good frequency selectivity for species communication.