Baihetan hydropower station, located on the Jinsha River in the Sichuan-Yunnan Block in Southwest China, is the second largest one after the Three Gorges hydroelectric power plant in China. Crustal stress state is an important geological factor affecting underground engineering, which is of great significance to the stability of underground chamber. For the long-term safe operation of hydropower station, the acoustic borehole televiewer with high resolution is utilized to log 7 holes in Baihetan right bank, and the borehole logging data revealed clear breakout phenomenon in seven borehole walls. The data of borehole breakouts are used to calculate the present orientation of principal stresses in engineering rock masses. The results show that the orientation of maximum horizontal principal stress (SH) in the right bank of Baihetan is NNE–SSW, which is consistent with the findings made by other scientists.