We report a simple method of improving the spatial profile of a passive Q-switched Nd:glass laser. In this method, a stimulated Brillouin scattering (SBS) cell has been used as an additional output coupler. The resultant spatial profile of the beam transmitted through the SBS cell has a super-Gaussian-like shape. Furthermore, the single-pulse operating range could be extended to a pumping level higher than that previously known as two- or three-pulse regions in conventional passive Q-switched lasers.