Abstract: By using closed “artificial climate control simulation experiment system” to controlling temperature and CO2 concentration, this paper studied the DOC mutative law of wetland soil of cattail and scirpus communities. The results showed both warming and doubling CO2 concentration increased the DOC content of wetland soil at varying degrees , warming had the greatest influences on the DOC content of wetland soil. Within 0-15cm soil layer, soil DOC concentration under warming or doubling CO2 concentrations were higher than that of combination of warming and doubled CO2 concentration, which indicated that the interaction of temperature and CO2 had antagonism on soil DOC in the soil surface, Within 15-30cm soil layer, the content of soil DOC was in order of ET > ETC > EC > CK. Under the same treatment, the content of soil DOC in cattail community was significantly higher than that of scirpus community, which indicated that both warming and doubling CO2 concentration could increase the content of soil DOC. Compared with scirpus community, cattail community was more conducive to increase the content of soil DOC.