In order to enhance the energy conversion efficiency and the power-load of two-cell stimulated Brillouin scattering (SBS) system, different liquid SBS mediums with almost similar Brillouin frequency shifts are used in the generator cell and the amplifier cell. The characteristics of the SBS system are investigated experimentally with Nd∶YAG Q-switched laser. Compared with two-cell SBS system with the same liquids, it can not only keep enough high-energy conversion efficiency, but also can effectively improve the system power-load ability and stability. The influences of the distance between the two cells on the SBS characteristics are analyzed in detail.