Abstract: Ferroelectric thin films Bi_3.15Nd_{0. 85}Ti_3-xZrxO₁₂ of B-site Zr substitution of Bi₄Ti₃O₁₂ were fabricated by sol-gel method in the paper. Test and analysis of B-site Zr substituted BNT thin films（ BNTZx） were done. The results show that residual polarization of BNTZ by Zr Substitution increased with the content of Zr⁴⁺ increasing first,it was the maximum when Zr⁴⁺ is 6%,then it was decreased with the content of Zr⁴⁺ increasing. But coercive voltage Vc has not nearly changed. Anti fatigue performance Of ferroelectric thin films Bi_3.15Nd_{0. 85}Ti_3-xZrxO₁₂ of B-site Zr substitution got the worst result than Bi₄Ti₃O₁₂ Thin Film.