Tb-doped lead zirconate titanate(Pb(Zr<TEX>$\_$</TEX>0.6/,Ti<TEX>$\_$</TEX>0.4/)O<TEX>$_3$</TEX>; PZT) thin films on Pt(111)/Ti/SiO<TEX>$_2$</TEX>/Si(100) substrates were fabricated by the sol-gel method. The effect on the structural and electrical properties of films measured according to Tb content. The dielectric and ferroelectric properties of Tb-doped PZT thin films were altered significantly by Tb-doping. The PZT thin film with higher dielectric constant and improved leakage current characteristic was obtained by adding 0.3 mol% Tb. The relative dielectric constant and the dielectric loss of the 0.3 mol% Tb-doped PZT thin film were 1611 and 0.024, respectively. Typical value of the swichable remanent poaraization(2Pr) and the coercive filed of the PZT film capacitor for 0.3 mol% Tb-doped were 61.4 <TEX>${\mu}$</TEX>C/cm<TEX>$^2$</TEX> and 61.9 kV/cm, respectively. Tb-doped PZT thin films showed improved fatigue characteristics comparing to the undoped PZT thin film.