We report on growth of 25%Bi(Ni0.5Ti0.5)O-3-75%PbTiO3 (25BNiT-PT) solid solution thin films and good electrical properties such as high remanent polarization, high dielectric constant, and low dissipation factor. The thin films prepared on Pt/TiO2/SiO2/Si substrates by pulsed laser deposition were well crystallized with a phase-pure perovskite structure. Well-saturated P-E hysteresis loops were observed with a much larger remanent polarization than that of corresponding ceramic counterparts reported before in literature. The remanent polarization P-r and coercive field E-c were 40.9 mu C/cm2 and 117 kV/cm, respectively, for the thin films annealed at 650 degrees C. The thin films had a high dielectric constant of about 400-500 and a low dissipation factor of 0.03 at a frequency of 1 kHz. The good polarization characteristics of the thin films are very significant for high-temperature ferroelectric device applications.