The BiScO 3 -modified (K 0.475 Na 0.475 Li 0.05 )(Nb 0.95 Sb 0.05 )O 3 lead-free piezoelectric ceramics were prepared using normal sintering technique. The effects of the BiScO 3 on the phase structure and electrical properties of the ceramics were systematically studied. These results show that the BiScO 3 -modified (K 0.475 Na 0.475 Li 0.04 )(Nb 0.95 Sb 0.05 )O 3 lead-free piezoelectric ceramics form stable solution with tetragonal structure, and the Curie temperature and the polymorphic phase transition of the ceramics decreased with increasing x. Furthermore, the effect of the polarization temperature (T p ) on the piezoelectric properties of the ceramics was also discussed. These results show that the piezoelectric properties of the ceramics strongly depend on the T p . The ceramics with x=0.005 poled at 30°C exhibit optimum piezoelectric properties (d 33 =280pC/N, k p =49%, ɛ r =1432, and tanδ=3.7%). These results indicate that the ceramic is a promising candidate material for lead-free piezoelectric ceramics.