Lead-free piezoelectric ceramics, 0.5Ba_0.8Ca_0.2TiO₃-0.5BaTi_0.8Sn_0.2O₃-0.02Pr₆O_11-xLa₂O₃ (x = 0–0.06), were fabricated by solid-state sintering method. The effects of La₂O₃ addition on the phase structure, microstructure and electric properties of the ceramics were studied. The X-ray diffraction and Raman spectrum analyses revealed that La³⁺ ions diffused into the lattice to form a stable solid solution. Rhombohedral and tetragonal phases coexisted in the ceramics for x = 0.02–0.06. The grain growth-inhibiting effect of La doping led to an obvious decrease in grain size of ceramics from 58 μm (x = 0) to 22 μm (x = 0.06). The electrical properties were optimized at x = 0.04 with high piezoelectric coefficient (558 pC/N), planar electromechanical coupling factor (52.2%) and remnant polarization (7.5 μC/cm²)_.