Side-chain polymer liquid crystals that possess mesogenic donor-pi-acceptor chromophores (azobenzene and stilbene derivatives) were synthesized, and the efficiencies of second harmonic generation (SHG) were investigated. SHG susceptibility was found to be stabilized in liquid crystalline polymers. Hyperpolarizabilities (beta) of chromophores of the polymers were also investigated by the hyper Rayleigh scattering method, and it was found that the beta value of the polymers was nearly twice of that of the corresponding monomers. The magnitude of the beta of polymers was affected by the length of the spacer unit that connects the chromophore (mesogen) to the polymer main chain.