Abstract: The desorption isotherms of uranium tritide samples that have been stored at ambient temperature for 0,460,610,or 1 720 d respectively under different desorption temperatures are measured. The experimental results show that the range,slope,and pressure of the plateau on the isotherm of each aged UT_x samples are kept essentially unchanged in comparison with that of unaged UT_x sample. Tritium heels left in the samples after desorption are negligible. No remarkable decrease in the rever-(sible) storage capacity for tritium is observed. It is concluded that the effect of tritium aging on tritium storage is very small, and uranium tritide seems suitable as a good medium for long-term storage of tritium.