The ferroelectric properties of the bismuth titanate niobate Bi7Ti4NbO21 thin film have been studied. The Bi7Ti4NbO21 thin film was successfully fabricated on platinized Si substrates by chemical solution deposition method. The crystallization of bismuth titanate niobate thin film was observed using an X-ray diffraction analysis (XRD). The hysteresis loop was observed a standardized ferroelectric test system. The thin him exhibits ferroelectric hysteresis with remnant polarization P-r = 5.65 mu C/cm(2) and coercive field E-c = 127 kV/cm.