Stimulated Brillouin scattering (SBS) is one of the most efficient methods to achieve optical phase conjugation. However, practical SBS phase conjugation applications is always accompanied pulse compression, re. sulting pulse waveform change. To obtain better waveform fidelity while applying the stimulated Brillouin scattering phase conjugate mirror, pulse control in stimulated Brillouin scattering process is investigated experimentally. By raising the energy density of the injected pump pulse, a higher transient gain is provided, and the stokes signal is generated earlier at time domain. With the control of pump intensity, the stokes pulse with high waveform fidelity is achieved.