Bismuth ferrite (BiFeO 3 ) has proven to be promising for a wide variety of microelectric and magnetoelectric devices applications. In this work, a dense (Ba 0.65 Sr 0.35 )TiO 3 (BST)/ (Bi 0.875 Nd 0.125 )FeO 3 (BNF)/BST trilayered thin film grown on Pt-coated Si (100) substrates was developed by the rf-sputtering. For comparison, single-layered BNF and BST were also prepared on the same substrates, respectively. The results show that the dielectric loses suppression in BST/BNF/BST trilayered thin films at room temperature but has enhanced ferromagnetic and ferroelectric properties. The remnant polarization (P r ) and coercive electronic field (E c ) were 5.51 µC/cm 2 and 18.3 kV/cm, and the remnant magnetization (M r ) and coercive magnetic field (H c ) were 10.1 emu/cm 3 and 351 Oe, respectively, for the trilayered film. We considered that the bismuth's volatilization was limited by BST bottom layers making the Bi/Fe in good station, and the action of BST layer in the charge transfer between BNF thin film and electrode led to the quite low leakage current and enhanced multiferroic property. The origin of the mechanism of the highly enhanced dielectric constant and decreased loss tanδ was discussed.Coatings 2019, 9, 502 2 of 8 fields [21,22]. The electric field control of magnetism requires deterministic control of the magnetic order, and the magnetoelectric coupling in multiferrous BiFeO 3 can be understood [23]. In addition, the others FE/MF heterostructured thin films and FE/MF(FE)/FE trilayered structural thin films were prepared [24][25][26][27], but these films still have a high leakage current density and a dissipation factor.In this work, Ba 0.65 Sr 0.35 TiO 3 , Bi 0.875 Nd 0.125 FeO 3 and Ba 0.65 Sr 0.35 TiO 3 -Bi 0.875 Nd 0.125 FeO 3 -Ba 0.65 Sr 0.35 TiO 3 thin films grown on Pt/Ti/SiO 2 /Si (100) substrates were prepared by radio frequency magnetron sputtering. The ferroelectric, ferromagnetic, and electrical properties of these film samples were investigated. The low dielectric loss, low leakage current density, and multiferroic properties enhancement mechanism of the sandwich structural thin films are also discussed.