Lead-free K0.5Na0.5NbO3-xwt% (0.4ZnO-0.6B2O3) ceramics were synthesized by conventional ceramics process. The co-doping of ZnO and B2O3 can decrease the sintering temperature of K0.5Na0.5NbO3 ceramics to 1000°C, and the samples show high relative density around 96%. X-ray diffraction (XRD) reveals that Co-doping of ZnO and B2O3 induces lattice distortion. Liquid phase is observed by scanning electron microscopy (SEM), which is resulted from the addition of ZnO and B2O3. The ceramics show better piezoelectric and dielectric properties with planar electromechanical coupling factor kp= 40.7%, piezoelectric constant d33=117pC/N, dielectric constant εT33/ε0=318.6, and loss tangent tanδ=0.034.