The Pb1-xSrx(Mn1/3Sb2/3)0.05Zr0.48Ti0.47O3 +0.25%CeO2+0.50%Yb2O3+0.15%Fe2O3(PMS-PZT, x=0, 0.02, 0.04, 0.06) ternary system hard piezoelectric ceramics were synthesized by the conventional solid-state reaction method. The effects of Sr-substitution on the phase structure and electrical properties of the PMS-PZT ceramics were systematically studied by X-ray diffractometer, quasi-static piezoelectric constant tester and ferroelectric tester. The experimental results show that both the PMS-PZT piezoelectric ceramics with and without Sr-substitution have a single tetragonal crystal structure. When x=0.02, PMS-PZT has the best performance: d33=415 pC/N, Qm=522, TC=291 ℃, kp=0.64, εr=1 304, Pr=11.32 μC/cm2, Ec=9.05 kV/cm.