Nitrogen (N) is an essential element for plant growth, and only inorganic N can be directly absorbed by plants. Thus N mineralization and its temperature sensitivity are of significance to the biogeochemical cycle and ecosystem function. In the present study, field experiments in combination with thermostatic cultivation were conducted to investigate the effects of thinning intensities[25%thinning (25%Th) and 50%thinning (50%Th)] and understory removal (UR) on soil N mineralization and its temperature sensitivity in Moso plantation. The results showed that 25%Th significantly increased the soil N ammonification rate (P < 0.01), but it decreased the nitrification rate (P < 0.01). By contrast, 50%Th and UR had significant effects on the nitrification rate, but not on the ammonification rate. Specifically, 50%Th remarkably increased the nitrification rate (P < 0.01), whereas UR decreased the nitrification rate (P < 0.01). Correlation analysis showed that there were negative correlations between the ammonification rate and soil organic carbon content (SOC), total nitrogen content and total phosphorus content; the soil nitrification rate showed positive correlations with SOC and soil water content, but negative correlation with ammonium nitrogen (NH₄⁺-N) content. Q₁₀ was used to indicate the correlation between temperature and N mineralization. 25%Th decreased the Q₁₀ of net N mineralization and ammonification, while UR increased that of nitrification. In general, Q₁₀ under different treatments were 1.17 and 1.36. In conclusion, 25%Th and understory conservation are beneficial to soil N supply in Moso plantation.