The effects of substrate temperatures and annealing temperatures on the microstructures and ferroelectric properties of PbZ $r_{0.52}$ $Ti_{0.48}$ $O_3$(PZT) thin fims prepared by pulsed laser deposition (PLD) were investigated. For this purpose, the PZT films were deposited at various substrate temperatures (400~$600^{circ}C$) with post annealing process in oxygen atmosphere. The single perovskite phase was formed at the deposition temperature of 500 to 55$0^{circ}C$ without post annealing and the PZT films deposited below 50$0^{circ}C$ formed the single phase with post annealing at $650^{circ}C$. The grain size of the films increased and the grain boundary of the films was clearly defined as the substrate temperature increased from 400 to 55$0^{circ}C$. The remnant polarization (Pr) and the coercive field (Ec) of the films deposited at 55$0^{circ}C$ and annealed at $650^{circ}C$ were 34.3 $mu$C/c $m^2$and 60.2 kV/cm, respectively.y.y.