Abstract: The ultrasonic testing is one of the elastic wave tests, its theory is from the theory of elastic wave propagation in solid media. In this method, the ultrasonic wave is from the artificial excitation vibration source to some certain media, such as rock, rock mass and concrete, etc., and the wave modulated by their physical characteristic is received in some distance, then acoustic parameters of wave such as velocity, amplitude, frequency, etc. are observed and analyzed. By this way, some problems in geo-engineering are solved.