Abstract: Acoustic televiewer is a geophysical logging system which utilizes acoustic travel time and amplitude parameters for borehole wall imaging. The system has such that characteristics:high image resolution, fast logging speed, working in turbid well fluid, data processing and analysis process relatively simple because of its perfect software with digital technology and configuration. It is an effective means to study the structure surface of the rock strata. In the evaluation of the rock mass stability of a copper-cobalt mine in Congo (DRC), the acoustic logging method is used to obtain the dominant structural surface of the rock mass. The reliable data are provided for determining the slope angle of the open mining pit and shear strength index of the rock mass. The principle and method of the RG Acoustic televiewer logging are introduced in this paper. And rock mass structure surfaces and fractures revealed by borehole in wall image were analyzed, taking DK02 as a example. Engineering practice shows that the acoustic television in deep rock mass in situ investigation has obvious advantages.