Abstract RBaCo2O5+δ (R=Sm, Eu, Dy, Gd, and Y) thick films were prepared by the solid state reaction followed by the spin-coating method. The oxygen resistivity sensor properties of these films were investigated in switching O2/N2 atmosphere. The results show that the RBaCo2O5+δ films are promising as oxygen resistance sensors at elevated temperature. Especially, DyBaCo2O5+δ film shows a fast response speed, high sensitivity and good repeatability at 600°C. The correlation between the sensor properties of RBaCo2O5+δ thick films and their oxygen intake/release properties is also discussed.