Nitrogen (N) deposition because of continuous anthropogenic emission of air pollutants, is one of three major drivers of global change. Elevated N deposition may lead to N saturation, soil acidification, plant nutrient imbalances, and even forest productivity decline. Nutrients released from litterfall decomposition represent a large part of the input to the soil, which has been studied extensively in forest ecosystems around the globe. However, the relationship between soil nutrient availability and litterfall remains largely unknown regarding nitrogen deposition, especially in subtropical forests in South China. In the present study, the litterfall and soil nutrients were determined in a nitrogen-loaded Chinese fir (Cunninghamia lanceolata (Lamb.) Hook) plantation forest. A field experiment with simulated N additions at three doses, N1 (60 kg N hm^-2 a^-1), N2 (120 kg N hm^-2 a^-1), and N3 (240 kg N hm^-2 a^-1), with N0 as the control (0 kg N hm^-2 a^-1), was conducted by adding the required amount of urea dissolved in 20 L water. This field experiment was initiated in January 2004 with continuous operation and was monitored for almost 13 years. Ten 1 m×1 m litter collecting frames were randomly set up in each plot in January 2004. Litterfall samples were collected monthly and mixed together into one sample per plot. We selected litterfall samples in June 2016 and separated them into fallen leaf, branch, and fruit. In total, there were 12 plots×3 components=36 samples. Soil samples were collected randomly at the depths of 0-20 cm, 20-40 cm, and 40-60 cm in each plot in June 2016, which together (4 treatment levels×3 doses×3 soil layers) constituted 36 samples. The ecological stoichiometry of fallen leaves, branches, and fruits, and soil available nutrients, such as ammonium N (NH₄⁺-N), nitrate N (NO₃^--N), alkali-hydrolyzed N, available P, available K were measured. Our results showed that N deposition increased N content by 35.27% in fallen leaves and 32.21% in fallen branches averagely. The high level of N addition (N3) decreased the carbon to N (C/N) ratio by 25.95% and 32.21% in fallen leaves and branches, respectively, but increased the N to phosphorus (N/P) ratio in fallen branches by 38.4% and in fallen fruits by 31.7%. Nitrogen loads produced no significant effects on litterfall C content, P content, or the C/P ratio. The concentrations of soil NH₄⁺-N and NO₃^--N increased significantly with increasing N deposition levels at all three soil depths, with stronger response from NO₃^--N. The N1 treatment significantly suppressed soil available K, whereas the N2 treatment significantly promoted soil alkali-hydrolyzed N at 0-20 cm, but N deposition showed no significant effect on soil available P. Pearson's correlation and redundancy analysis (RDA) between litterfall ecological stoichiometry and soil available nutrients indicated that litterfall P concentration (Monte Carlo (999), P=0.018) and C/P ratio (P=0.037) were the major determinants of soil available nutrients. Negative relationships exited between the litterfall C/N ratio, C/P ratio, and soil available nutrients, which suggested that higher ratios were unfavorable to the accumulation of soil available nutrients.