Bismuth layer-structured ferroelectric ceramics of (1-x)Na0.5Bi2.5Nb2O9-xLiNbO(3) (NBN-LN, 0 < x < 0.2) were synthesized by a traditional solid-state reaction. The effects of LN addition on the microstructure and electrical properties of ceramics were studied carefully. It was found that the ceramics with x < 0.10 have a bismuth oxide layered structure. With the increasing of LN addition, the mechanical quality factor Q(m) firstly increases, and then decreases with a maximum value of 4820 at x=0.02. The Curie temperature T-c increases gradually and the electrical properties of NBN-based ceramics are improved significantly by the addition of LN. The piezoelectric constant d(33), dielectric loss tan delta, Curie temperature T-c, and remanent polarization P-r of 0.90Na(0.5)Bi(2.5)Nb(2)O(9)-0.10LiNbO(3) ceramics were found to be 21 pC/N, 0.16%, 789 degrees C, and 7.37 mu C/cm2, respectively. Thermal annealing and aging studies indicate that the NBN-LN system possesses stable piezoelectric properties, demonstrating that the NBN-LN ceramics are the promising candidates for high-temperature applications.