The Sr based ceramic thin films were deposited on Si substrate by RF magnetron sputtering method. And Sr based thin films were annealed at 500～700℃ using RTA. The surface roughness showed about 2.4 nm in annealed thin film at 600℃. The capacitance density of Sr based thin films were increased with the increase of annealing temperature. The maximum capacitance density of 0.6 ㎌/㎠ was obtained by annealing temperature at 700℃. The voltage dependence of dielectric loss showed about 0.02 in voltage ranges of -10～＋10 V. The leakage current density of annealing temperature of 600℃ was the 4.0×10-6 A/㎠ at applied voltage of -5～＋5 V.