When the Y0.5Tb0.5BaCo4O7+δ ceramic powder is heated to 200–380 °C in oxygen atmosphere, it can adsorb oxygen remarkably. The adsorbed oxygen could be released by raising temperature over 420 °C or by switching the atmosphere from oxygen to nitrogen. In a temperature cycle between 360 °C and 440 °C, the relative mass change of the Y0.5Tb0.5BaCo4O7+δ sample can reach 4.4% of its original mass, and shows high efficiency and stable oxygen adsorption/desorption reproducibility. However, the oxygen adsorption/desorption efficiency in the cycles switched between oxygen and nitrogen atmosphere is poor. The large adsorption capacity, the fast adsorption/desorption speeds, and the easy regeneration of Y0.5Tb0.5BaCo4O7+δ absorbent under temperature cycles make it to be a highly potential candidate in air separation and oxygen removal.