(1 − x)(K_0.5Na_0.5)_0.95Li_0.05Nb_0.93Sb_0.07O₃-xSrZrO₃ ((1 − x)KNLNS-xSZ) lead free piezoelectric ceramics have been prepared by the conventional solid state reaction method, via adjusting the orthorhombic–tetragonal phase transition temperature to near room temperature with doping SrZrO₃, and the effects of SrZrO₃ content on polymorphic phase transition have been investigated. These results show that the phase structure of the ceramics was changed from orthorhombic to tetragonal at x ≥ 0.02 mol, and the orthorhombic–tetragonal phase transition temperature was modified to around room temperature with increasing SrZrO₃. Remarkable piezoelectric and ferroelectric properties has been obtained in (1 − x)KNLNS-xSZ system with x = 0.02, which showed a piezoelectric parameter of d₃₃ = 256 pC N⁻¹, Curie temperature T_c = 270 °C, strain levels of 0.16% at 50 kV cm⁻¹, remnant polarization P_r = 24.9 μC cm⁻² and coercive field E_c = 10.6 kV cm⁻¹.