Abstract: Tritium in off-gas is oxidated to tritium water by catalyzer at high temperature in a dry carrier Argon gas with a little hydrogen, and is adsorbed by distilled water or suitable dryer. Oxidation rate of catalyzer for H 2 and HT is near 100% at 400 ℃ and more that 99% at 500 ℃, respeclively. Tritium release rate from three types molecular seives which adsorbed tritium water is found to be about (1.9～5.5)×10 -6 d -1 ·g -1 , the smallest one is for 4A-Na-type molecular seive and the largest one is for 5A-Ca-type molecular seive. The chemical state of released tritium from three types molecular seives is mainly in the form of HTO, and content of HT is less than 1.2%. Storage atmosphere of tritide molecular sevies greatly affects the tritium release. Release rate of tritium in pure argon gas is less than that in argon gas with 2% hydrogen.