Abstract: We introduce basic principles and measuring procedures of two geo-stress measuring methods, the hollow package triaxial gauges and the borehole slotter. Meanwhile, comparative analysis of the applicability of two relieving stress testing methods was carried out. The two different stress relieving methods were applied to the in-situ stress test of the side wall in the diversion tunnel of Jinping-I hydropower plant, and comparative tests were carried out in the same borehole. The measuring results of both methods were consistent. The stress value error was less than 20%, and the maximum principal stress of cross section drilling azimuth error was 20 degrees. So the borehole slotter method can be used for high stress measurement of underground projects in western China that usually encounters the conditions such as deep buried tunnels and high or extremely high stress conditions.