In this study, [Li0.04(Na0.5K0.5)0.96](Nb0.86Ta0.10Sb0.04)O3 + xSrO (x=0, 0.0025, 0.005, 0.0075) ceramics were synthesized by the conventional mixed oxide method. The X-ray diffraction patterns demonstrated that ceramics possessed single perovskite structure. The SEM images indicate that microstructure can be obviously affected by a small amount of added SrO. The phase transition temperature tetragonal-cubic(T(c)) and orthorhombic -tetragonal(T(o-t)) shifts downward and upward with the increase of Sr addition, respectively. The excellent piezoelectric properties of d33=170[pC/N], k(p)=0.37, Q(m)=64.12, T(o-t)=153℃ and T(c)=370℃ were obtained from the 0.25 mol% Sr added ceramics sintered at 1,120℃ for 1 h.