This paper presents a study of the hydrogen and oxygen isotopic compositions and distribution of tritium contents in hot spring water collected from the Changbaijulongquan spring in th e Tianc hi volcanic region, Changbai Mountains. The characteristics of h ydrogen and oxygen isotopic compositions indicate that the hot spring water is o riginated from the meteoric water. The tritium content in the groundwater gradua lly red uces from south to north, which indicates that the groundwater migrates from so u th to north and recharged from the mountainous area south of the hot spring area .The age of the hot spring water is about 40 a and the migratio n rate of the groundwater is about 7.5 m/a.