Ta doped PZT thin films were prepared by a reactive sputtering method with a 3-gun magnetron co-sputter, and effects of Ta doping on physical and electrical properties of the films were studied. Within the doping range of 0 to 3.6 at%, Ta doping enhanced the crystallographic orientation of (110), but reduced that of (100). Ta doped PZT had a larger grain size of about 20 ${mu}{ extrm}{m}$ compared with that of 5 ${mu}{ extrm}{m}$ for un-doped PZT. Pits and holes of PZT films which used to appear with annealing at high temperature due to evaporation of PbO were much suppressed with addition of Ta. The leakage current could be reduced down to 1.27$ imes$10-8 A/$ extrm{cm}^2$ and the charge storge density as large as 25.8$mu$C/$ extrm{cm}^2$ was obtained.