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Ferroelectric Bi2.9Pr0.9 Ti3O12/La0.67Sr0.33MnO3 (BPT/LSMO) films are fabricated on Pt(111)/TiO2/SiO2/Si substrates by rf-magnetron sputtering method. The influences of the LSMO deposition conditions and LSMO layer thickness on properties of BPT thin films are studied. The LSMO layer deposited at 300℃ and 450℃ favours preferred (117) orientation of BPT films, while deposited at 600℃ for LSMO layer leads to strong (111)- preferred orientation of BPT film. With the LSMO buffer layer, the films exhibit improved ferroelectric properties and Pt/BPT/LSMO(2Onm)/Pt capacitor shows the largest remnant polarization Pr of 18.4μC/cm2 at 14 V. A similar change in dielectric constant with the increase of LSMO layer thickness is also observed and the highest dielectric constant of 342.7 is obtained for the Pt/BPT/LSMO (20 nm)/Pt film. Compared with the Pt/BPT/Pt film, the Pt/BPT/LSMO/Pt films exhibit better fatigue endurance after 5 x 109 switching cycles. Moreover, the LSMO layer has apparent effect on leakage current density and the Pt/BPT/LSMO (20 nm)/Pt film exhibits the lowest leakage current density.