Single-phase multiferroic BiFeO_3 and Bi_(0.9)(La/Nd)_(0.1)FeO_3(doped with rare earth ions La~(3+) and Nd~(3+)) films grown on(111)-Pt/Ti/SiO_2/Si substrate were prepared via sol-gel method and a subsequent rapid thermal process. The phase composition, microstructure, ferroelectric, dielectric, ferromagnetic properties were investigated, and meanwhile, the in-plane magnetoelectric(ME) coupling effects of the films were reported and studied for the first time in this work. Structural characterization by X-ray diffraction and scanning electron microscopy showed that both BiFeO_3 and Bi_(0.9)(La/Nd)_(0.1)FeO_3 exhabited a rhombohedral structure with(111) preferred orientation. The results of the physical properties indicated that the introduction of rare earth ions improved significantly the polarization, magnetization and dielectric properties than the undoped BiFeO_3 crystals, and it enhanced effectively the in-plane ME coupling(the ME coupling coefficient αE increased from 0.13 in the pure BiFeO_3 to 0.21 in Bi_(0.9)La_(0.1)FeO_3 and 0.34 V/(Oe·cm) in Bi_(0.9)Nd_(0.1)FeO_3). The mechanism of these phenomena was investigated systematically. Single-phase multiferroic BiFeO_3 and Bi_ (0.9) (La / Nd) _ (0.1) FeO_3 doped with rare earth ions La ~ (3+) and Nd ~ (3+) films grown on (111) -Pt / Ti / SiO_2 / Si substrate were prepared via sol-gel method and a subsequent rapid thermal process. The phase composition, microstructure, ferroelectric, dielectric, ferromagnetic properties were investigated, and meanwhile, the in-plane magnetoelectric (ME) coupling effects of the films were reported and studied for the first time in this work. Structural characterization by X-ray diffraction and scanning electron microscopy showed that both both BiFeO_3 and Bi_ (0.9) (La / Nd) _ (0.1) FeO_3 exhabited a rhombohedral structure with (111) preferred results. The results of the physical properties indicated that the introduction of rare earth ions improved significantly the polarization, magnetization and dielectric properties than the undoped BiFeO 3 crystals, and it enhanced effectively the in-plane ME coupling (the ME coupling coefficient α E increased from 0.13 in th e pure BiFeO_3 to 0.21 in Bi_ (0.9) La_ (0.1) FeO_3 and 0.34 V / (Oe · cm) in Bi_ (0.9) Nd_ (0.1) FeO_3) .The mechanism of these phenomena was investigated systematically.