The invention discloses a transducer for detecting a rock mass acoustic wave. The transducer comprises a transmitting transducer (1), a receiving transducer (2), a rigid connection pipe (3), a measuring bar (4), a hydraulic pump (8) and an acoustic wave collecting device (9), wherein the transmitting transducer (1) is connected with the receiving transducer (2) through the rigid connection pipe (3); the top end of the transmitting transducer (1) is connected with the measuring bar (4). The transducer has the advantages that dry hole detection of an acoustic wave test is achieved under the condition that a coupling agent does not need to be introduced through direct contact of a scalable hydraulic contact and hole wall rock mass of a detection hole; the transducer is not affected by water supply for construction, and drilling azimuth and angle, and can adapt to various detection conditions on the scene; the coupling pressure is controlled through hydraulic equipment with a pressure gage, and the consistence of the coupling conditions can be ensured. The effect of the coupling agent is removed, and the consistence of the coupling conditions is ensured, so that the data in the aspects of acoustic wave amplitude, frequency spectrum and the like also can be obtained besides the condition that the waveform jump point can be accurately judged to obtain acoustic wave velocity data in the acoustic wave test by using the device provided by the invention.