The La3+ and Nb5+ were used as the nonequivalent substitution of A and B ions in PZT ceramics, the effects of A/B vacancies ratio caused by the unequal ions doping of A and B sites on the performance of ［(Pb0.93La0.07)1-α□α］［(Zr1-y-zTiyNbz1-β□β］O3 （PLZTN） ceramics were investigated. The key factors that affect the properties of PZT ceramics were found when the A and B sites were simultaneously doped and substituted. The piezoelectric ceramics prepared in the range of values of y、z、α、β had a relatively pure perovskite structure and exhibited the characteristics of relaxation ferroelectrics. When r(Ti)/r(Zr)=39/61, z=0.02 and α/β=2/1, the PLZTN ceramics sample presented the optimal piezoelectric performance. The piezoelectric constant d33 and plane electromechanical coupling coefficient kp were found to be 800 pC/N and 71.85%, respectively. The materials showed a large electrostrictive coefficient. The k31 of the piezoelectric thin bar (0.22 mm×7.8 mm×45 mm) was found to be 046. The piezoelectric bimorphs were assembled by these ceramic thin bars, and the free end thrust of the cantilever beam was 32 grams and the unloaded displacement was 0.8 mm under the voltage of 180 V. The ceramics might be ideal materials for the piezoelectric Jacquard applications of the warp knitting machine.