Ferroelectric Sr0.8Bi2.4Ta2O9 stock solutions were prepared by MOD(Metaloganic Decompostion) process. The phase transformation for the layered perovskite of the SBT thin films by changing RTA(Rapid her-mal Annealing) temperatuer from 700$^{circ}C$to 780$^{circ}C$ were observed using XRD and SEM. Layered perovskite phase began to appear above 740$^{circ}C$ and then SBT thin films were annealed at 800$^{circ}C$ for 1hr for its com-plete crystallization. The specimens showed well shaped hysteresis curves without post annealing that car-ried out after deposition of Pt top electrode. The SBT thin films showed the asymmetric ferroelectric pro-perties. It was confirmed that the properties were caused by interface effect to SBT and electrode by leak-age current density measurement and asymmetric properties reduced by post annealing. At post annealing temperature of 800$^{circ}C$ remanant polarization values (2Pr) were 6.7 9 ${mu}$C/cm2 and those of leakage current densities were 3.73${ imes}$10-7 1.32${ imes}$10-6 A/cm2 at 3, 5V respectively. Also bismuth bonding types of SBT thin film surface were observed by XPS.