The application of Golay pulse coding technique on Brillouin optical time-domain reflectometer (BOTDR) in a radiation environment is experimentally analyzed. By applying Golay pulse codes on the BOTDR system in the radiation experiment, the enhancement of detection range, accuracy of Brillouin frequency shift (BFS), and reduction of stress measurement error are characterized. By using 64-bit Golay coding, signal-to-noise ratio can be improved significantly and the variation of BFS is more accurate. These results are beneficial for the application of the Golay pulse code technique on BOTDR in the space station.