The self-heterodyne detection Brillouin optical time domain reflectometer (BOTDR) system using broad-band laser is proposed to reduce coherent Rayleigh noise and improve the system performance. Compared with the system with narrow-band laser, the stimulated Brillouin scattering (SBS) threshold can be improved by about 3 dB. The experi-mental results of the narrow-band laser measurements for three times independently and the broad-band laser meas-urement for one time are compared. The root-mean-square (RMS) errors of Brillouin linewidth for two systems with narrow-band laser and broad-band laser are 6.9 MHz and 2.7 MHz, respectively, and the RMS errors of temperature for the heated fiber are about 1.3 °C and 0.7 °C. With the broad-band laser, signal-to-noise ratio (SNR) of the un-heated fiber is approximately equivalent to that of the integrated three independent Brillouin signals for the narrow-band laser, and the results are believed to be beneficial for performance improvement and measurement time reduc-tion.