Global warming and nitrogen deposition are two main global change drivers, often occurring simultaneously. However, most of related studies referred to only single factor. Fine root functional traits such as morphology and chemical properties play a key role in promoting plant nutrient acquisition and forest biogeochemistry cycling. The effects of climate warming, N deposition and their interactions on fine root morphology and chemical properties remain unclear. To explore the effects of warming and N addition on the morphological and chemical characteristics of fine roots of Cunninghamia Lanceolata. We conducted a two-factor experiment of soil warming and nitrogen addition, which consisted control (CT), low nitrogen treatment (LN), high nitrogen treatment (HN), warming treatment (W), warming and low nitrogen treatment (WLN), warming and high nitrogen treatment (WHN), at the Forest Ecosystem and Global Change Research Station of Fujian Normal University, Chenda, Sanming, Fujian Province. The results showed that:(1) the warming significantly increased fine root diameter (D). The interaction of warming and N addition had significant effects on the specific root length (SRL), specific surface area (SRA) and root tissue density (RTD) of fine roots. Compared with CT, the W and WHN reduced fine root SRL and SRA; there was no significant difference in RTD of fine roots among different treatments. The interaction of N addition and order had significant effects on fine root SRA. Low nitrogen addition only increased SRA of first order root significantly. (2) The interaction of warming and N addition had a significant effect on fine root C concentration, and only WHN significantly increased fine root C concentration. The interaction of N addition and order had significant effects on fine root concentration. The fine root C concentration of high N addition was significantly higher than that of low N addition. The interaction of warming, N addition and order had significant effects on fine root N concentration and C:N. Compared with CT, the effects of LN and HN on fine root N content and C:N varied with the order; The W, WLN and WHN significantly increased the fine root N concentration and decreased the fine root C:N. Compared with high-order root, low-order root N concentration and C:N were more sensitive to the effects of W and WLN. The results showed that the responses of fine root morphology and chemical characteristics to warming, N addition and their interaction were different, and the differences were mainly regulated by fine root branch order and N addition level; The warming and N addition promoted fine root N concentration and decreased fine root C:N, which would contribute to understand the subsurface nutrient cycling and the response of C sequestration to global environmental change in subtropical forests.