Abstract: Three temperature gradients of 36, 24, and 12 ℃ were set for culture test in 3 layered litter of 5 stages of grass, shrub, Betula platyphylla forest, Betula platyphylla-Larix gmelinii forest and Larix gmelinii forest under forest succession after the fire in Greater Khingan Mountains based on the 'space instead of time' method. The DOC concentration and residual amount of litter precipitation were measured, and the dynamics of litter decomposition and release of DOC in different litter layers in different forest succession stages were analyzed. Results show that the litter decomposition rate and DOC release increase first and then decrease with the succession sequence. As the temperature increases, the rate of litter decomposition increases and the amount of DOC released increases. Litter decomposition rate and DOC release amount appear as undecomposed layer larger than leaver layer and humus layer. Forest succession, temperature, and litter stratification have important effects on litter decomposition and DOC release.