We fabricated lead-free (K0.44Na0.52Li0.04)(Nb0.86Ta0.10Sb0.04)O3 (LF4) ceramics by using a citric-acid-assisted modified (CAM) sol-gel method. The CAM sol-gel method is based on a solution approach, which ensures a uniform distribution and atomic-level mixing of the reactants and the gelling agents. The optimized calcination temperature for the LF4 ceramics fabricated by using the CAM sol-gel method was about 200 °C lower than that for ceramics fabricated using the solid-state reaction method. The LF4 ceramics had better ferroelectric and piezoelectric properties than those produced using the solid-state reaction method.