It is essential to analysis of hydrogen isotopes in the fuel cycle system of fusion reactors,gas chromatography(GC)was found to be an effectively analytical technique.Compared with conventional GC,the high-precision GC with a cryogenic column could achieve fairly good performance to reduce the retention time. It is essential to analysis of hydrogen isotopes in the fuel cycle system of fusion reactors, gas chromatography (GC) was found to be an appropriate analytical technique. Compared with conventional GC, the high-precision GC with a cryogenic column could achieve fairly good performance to reduce the retention time.