This study investigated the effects of temperature,moisture and grazing on soil nitrogen mineralizationto understand the impact of human activities on soil nitrogen mineralizationand provide a reference for predicting the effects of climate change on soil nitrogen mineralization in Naqu prefecture of Tibetan. Soil samples were collected from two kinds of sample areas (grazing prohibition and grazing plot) in an alpine meadow in Naqu prefecture of Tibetan. Then laboratory incubation with five different temperature gradients (5, 10, 15, 20 and 25 ℃) and two different moisture levels (40% and 60% saturated soil moisture, SSM) were conducted. Soil were sampled three times to determinesoil inorganic nitrogen and other nutrient contents during the 41 days of incubation period. Results showed that the main component of soil inorganic nitrogen is nitrate nitrogen, and the ratio of nitrate nitrogen to inorganic nitrogen is 80.2%, 94.5% and 95.9% in different incubation stages, respectively. Soil mineral nitrogen production were significantly positively correlated to the temperature and was weakly positively correlated with moisture in grazing prohibition plot and significantly negatively correlated to moisture in grazing plot. With the change of incubation time, the correlation between soil mineral nitrogen production and temperature increased, and the correlation with moisture decreased under two management practices. Soil net nitrogen mineralization rate was weakly correlated to the moisture but was significantly positively related to the temperature and reached the maximum of 1.91 mg /(kg·d) at 25℃,which was 70.7%, 174.3%, 168.6%, 308.3% higher than that at 20, 15, 10,5 ℃, respectively. There weresignificant interactions between the temperature and moisture on net nitrogen mineralization in the early stage of grazing prohibition conditions and the optimal models was N =-14.905-0.011T +62.247M +0.005T2-60.02M2-0.145TM. Fitting exponential model suggested that the substrate quality in grazing plot was better than in grazing prohibition plot and the temperature sensitivity was lower in grazing plot. There was no significant difference on soil net nitrogen mineralization rate between the two plots. The temperature rise will accelerate the process of soil nitrogen mineralization, which will increase the inorganic nitrogen content in soil fora short time,while the effect of humidity will not be significant under the tendency of increasing the temperature and precipitation. Studies have shown that moderate grazing is a more reasonable method of land use in the region. It not only helps to make full use of grassland resources, but also better responds to the effects of global climate change.