【Objective】 As affected by anthropogenic activities, such as greenhouse agriculture that emits greenhouse gases, the global mean surface temperature rose by about 0.85 °C over the period of 1880—2012; and nitrogen deposition in China increased significantly by 0.41 kg•hm-2 with each passing year over the period from 1980 to 2010. In the context of global warming, soil dissolved organic matter (DOM) attracts more and more attention due to its important role affecting global carbon and nitrogen balance, which is of great significance to the ecological environment. This study aims to investigate effects of soil warming and nitrogen addition on content and structure of soil DOM in the soil of Cunninghamia lanceolata plantations in subtropical China. 【Method】 In 2014—2015, a mesocosm field experiment was carried out in a Cunninghamia lanceolata plantations in subtropical China. The experiment was designed to have six treatments, that is, (1) CT (no warming and 0 kg•hm ^-2•a^-1); (2) W (+5 ℃, 0 kg•hm ^-2•a^-1); (3) HN (no warming and 80 kg•hm ^-2•a^-1); (4) LN (no warming and 40 kg•hm^-2•a^-1); (5) WHN (+5 ℃ and 80 kg•hm ^-2•a^-1); and (6) WLN, (+5 ℃ and 40 kg•hm^-2•a^-1). Soil samples were collected in January 2015 (dry season) and April 2015 (rainy season), separately for analysis of DOM. 【Result】Results show that soil warming increased the content of DOM, but decreased its aromaticity index and humification index, which might be attributed to the effect of high temperature promoting conversion of SOM (soil organic matter) into DOM. The impact of nitrogen addition on DOM structure showed a seasonal pattern. In the dry season, addition of nitrogen increased both the content and aromaticity index of DOM, while in the rainy season, it increased the content of DOM, but reduced its aromaticity and humification index significantly. Under the joint effect of high temperature and nitrogen addition, the DOM peaked in content and got simpler in structure. Besides the direct impacts of temperature and nitrogen content, soil moisture and pH were also key factors cotrolling DOM dynamics as revealed by RDA (redundancy analysis). 【Conclusion】Based on the findings of the experiment, it could be concluded that 1) Both warming and application of nitrogen affect soil pH, thus making it easier for SOM to convert into DOM. Since the dissolution of organic matter in soil solution is mostly endothermic, warming accelerates the dissolution of plant residues and SOM into DOM; while nitrogen addition can also increase soil DOM content by promoting plant growth. 2)The effects of warming and nitrogen addition on soil DOM show a strong seasonal pattern, indicating that the influences of future global warming and nitrogen deposition will vary with environment conditions from region to region. Hence, more experiments should be done to further explore impacts of warming, nitrogen addition and their interaction on soil DOM, and some other environmenatl variables should be taken into account to attain a more profound comprehension of carbon and nitrogen cycling under a changing global climate.