To investigate the response of soil respiration of Lithocarpus glabra and Castanopsis sclerophylla seedlings for increased nitrogen deposition, a field experiment with 4 simulated nitrogen deposition levels, 0kg · hm^-2 · a^-1, 60 kg · hm^-2 · a^-1, 120 kg · hm^-2 · a^-1 and 240 kg · hm^-2 · a^-1, were conducted. The measurement of soil respiration was made by a LI-8100 soil CO₂ efflux system. The soil temperature at 10 cm depth and soil moisture at 5 cm depth also were recorded at the same time. Results show that: (1) The soil respiration rate of Lithocarpus glabra and Castanopsis sclerophylla seedlings were fluctuated significantly under different nitrogen deposition levels. To Lithocarpus glabra seeedling, the mean rate of soil respiration was (4.014±0.812)μmol · m^-2 · s^-1 under 60 kg · hm^-2 · a^-1 level and increased 5% comparing with control level (0 kg · hm^-2 · a^-1). The mean rate of soil respiration were (2.653±0.681)μmol · m^-2 · s^-1 and (2.592±0.736)μmol · m^-2 · s^-1 under 120 kg · hm^-2 · a^-1 and 240 kg · hm^-2 · a^-1 level, and reduced 27% and 29% respectively comparing with control level (0 kg · hm^-2 · a^-1). The mean rate of soil respiration of Castanopsis sclerophylla seedling, was (5.170±0.689)μmol · m^-2 · s^-1 under 60 kg · hm^-2 · a^-1 level and increased 45% comparing with control level ( 0 kg · hm^-2 · a^-1). The mean rate of soil respiration were (3.563±0.402)μmol · m^-2 · s^-1 and (3.466±0.994)μmol · m^-2 · s^-1 under 120 kg · hm^-2 · a^-1 and 240 kg · hm^-2 · a^-1level, as well as reduced 7% and 8% respectively. (2) The relationship between soil respiration and soil temperature at 10 cm of Lithocarpus glabra seedling was significant (R²=0.811,P=0.001) under 240 kg · hm^-2 · a^-1 level, which could be described by exponential equation. While, under the 4 simulated nitrogen deposition levels, the relationships between soil respiration and soil temperature at 10 cm of Castanopsis sclerophylla were not significant. However, both of Lithocarpus glabra and Castanopsis sclerophylla, the relationship between soil respiration and soil moistures at 5 cm depth also were not significant. The relationships between soil respiration and soil temperature at 10 cm and soil moisture at 5 cm depth were analyzed by multiple regression equation. The regression equations had more predicative capability than those using only temperature or moisture as a single independent variable at the P=0.05 level,. The regression equations of Lithocarpus glabra and Castanopsis sclerophylla soil respiration can interpret the results 89.9%-85.4% and 87.9%-78.7% respectively. the R² values of Lithocarpus glabra seedling soil respiration tended to decrease with nitrogen deposition, but the R² values of Castanopsis sclerophylla soil respiration tended to increase with nitrogen deposition in 60 kg · hm^-2 · a^-1 and 120 kg · hm^-2 · a^-1, and decrease with 240 kg · hm^-2 · a^-1. (3) The Q₁₀ values at four different nitrogen treatment levels of Lithocarpus glabra and Castanopsis sclerophylla seedlings were 2.29、1.95、1.59 and 1.46、1.41、1.76 respectively. Compared with which at control level, the Q₁₀ values of Lithocarpus glabra seedling soil respiration tended to decrease with nitrogen deposition, but the Q₁₀ values of Castanopsis sclerophylla seedling soil respiration tended to decrease with nitrogen deposition in 60 kg · hm^-2 · a^-1 and 120 kg · hm^-2 · a^-1, and increased with 240 kg · hm^-2 · a^-1. But Lithocarpus glabra and Castanopsis sclerophylla soil respiration, the Q₁₀ are all lower than the control level (0 kg · hm^-2 · a^-1). Both of them, the Q₁₀ values at control level are 2.64 and 1.78 respectively. The results indicated that nitrogen deposition is an important factor in affecting soil CO₂ efflux of Lithocarpus glabra and Castanopsis sclerophylla seedlings.