An apparatus for testing a performance of a shock wave generator according to an embodiment of the present invention includes: a medium tank which defines a test space which is filled with cavitation medium; an acoustic window which is provided to the medium tank and allows a shock wave to be irradiated into the cavitation medium; a sensor device which detects a signal of the shock wave; a photographing device for photographing an image of a group of cavitation bubbles produced in the test space; an illumination device which is disposed to illuminate the cavitation medium; an image processing portion and an image analyzing portion which estimates an exposure information of the shock wave based on image information of the group of the cavitation bubbles obtained by the photographing device; a performance validation portion validating the performance of the shock wave generator based on the estimated exposure information of the shock wave and a prestored database; and a controller controlling an operation of the illumination device and the photographing device during an irradiation of the shock wave and comprising a user interface and a data processing portion.