Ferroelectric Bi_4-xLa_xTi₃O₁₂ thin films were prepared by chemical solution deposition using bismuth acetate, lanthanum acetate and titanium isopropoxide as precursors. The BLT thin films were deposited as a function of lanthanum composition. The structure and the surface morphology of the BLT thin films were characterized by x-ray diffraction and field emission scanning electron microscopy. The electrical measurements were performed using a RT66A. The BLT films doped with x=0.75 were fond to exhibit better electrical properties than those doped with other La compositions. The remanent polarization(2P_r) and the coercive voltage(V_c) of BLT thin film with x-0.75 were 11.1 μC/cm² and 1.3 V.