Palladium is an important functional material in tritium treating technology, tritium decay and its product,helium-3 will decrease the properties of hydrogen storage of palladium. The PcT curves of absorbing/desorbing protium and deuterium were measured by the varying temperature method for aged palladium after 1.6 years tritium storage, the experimental results of fresh sponge palladium were provided for comparison in this work, furthermore, thermodynamics of the aged palladium absorbing/desorbing protium and deuterium was analyzed. Comparing with the fresh palladium, tritium aging compel a phase zone to shift right, decreases the plateau pressures of aged Pd-H and Pd-D systems as narrowing down the scope of the plateau pressures, further analyzing shows that the tritium aging weakens the hysteresis effect of palladium absorbing/desorbing hydrogen, affects the enthalpy and entropy changes of the formation of palladium hydride.