Bilayered thin films consisting of Pb(Mg1/3Nb2/3)O-3-PbTiO3 and (Bi3.15Nb0.85)Ti3O12 (PMN-PT/BNdT) layers have been successfully deposited on Pt/Ti/SiO2/Si substrate by RF sputtering. Their ferroelectric and dielectric behaviors can be tailored by varying the thicknesses of the two constituent ferroelectric layers. An enhancement in both remanent polarization and fatigue resistance is observed by increasing the layer thickness of BNdT, which also leads to an increase in coercive field. The bilayered ferroelectric thin films demonstrate electrical behaviors in association with space charge at low frequencies, which can account for the observed ferroelectric and fatigue properties, as confirmed by frequency and impedance studies.