【Objective】 Moso bamboo is a typical type of forest resource widely distributed in South China. Its expansion, however, has caused a number of ecological problems, especially emission of soil N₂O and CO₂ in the groves as affected by nitrogen deposition, which has rarely any research papers, let alone in-situ field observation data. 【Method】In this study, the static chamber technique was used to monitor N₂O and CO₂ emission rates, cumulative N₂O and CO₂ emissions and their responses to simulated nitrogen deposition in pure moso bamboo forest, moso bamboo - Japanese cedar mixed forest and pure Japanese cedar forest in Lushan Mountain, Jiangxi Province. 【Result】Results show: (1) the content of NH₄⁺-N, content of NO₃^--N, and pH in the mixed forest soil was 14.39 mg•kg^-1, 8.65 mg•kg^-1, and 4.88, respectively, significantly higher than their respective ones in the Japanese cedar forest soil (i.e. 9.75 mg•kg^-1, 5.58 mg•kg^-1 and 4.05), but the former (236.5 mg•kg^-1) was much lower than the latter (382.0 mg•kg^-1) in DOC content; (2) the cumulative N₂ O emission in the mixed forest (393.6 mg•m^-2) was significantly higher than that in the moso bamboo forest (202.5 mg•m^-2) and that in the Japanese cedar (192.8 mg•m^-2), while the cumulative CO₂ emission in the mixed forest (4 655 g•m^-2) was significantly higher than that in the Japanese cedar forest (2 815 g•m^-2); and (3) simulated nitrogen deposition had no significant effect on CO₂ emission rate and cumulative CO₂ emission in the three types of forest soils, but significantly increased cumulative N₂O emission in the Japanese cedar forest soil and mixed forest soil. 【Conclusion】 All the findings indicate that the soils varied in physicochemical property and N₂O and CO₂emission characteristics with the expansion of moso bamboo. Expansion of moso bamboo did increase N₂O and CO₂ emission from the soils to a certain extent. However, when the expansion completed, like in the moso bamboo forest, emissions of N₂O decreased significantly, while emission of CO₂ did not change much. Meanwhile, nitrogen deposition promoted N₂O emission from the Japanese cedar forest soil (no bamboo intruding) and the mixed forest soil (early stage of moso bamboo expansion), but had no significant effect on CO₂emission. It is, therefore, suggested that in management of moso bamboo expansion in subtropical China under future meteorological conditions, it is essential to take into account effects of composition and structure of the ecosystem and other various affecting factors.