Researches on soil CO_2 fluxes in alpine meadow of permafrost regions could facilitate accurate estimation of annual total fluxes of the soil CO_2 in the Tibetan Plateau. It is also of great significance to reveal soil carbon cycles and its response to global climate change in the plateau. An alpine meadow site in the permafrost region of the upper reaches of the Shule River in the northeast margin of the Tibetan Plateau was selected as a study area, and soil CO_2 fluxes were regularly measured using static chamber/gas chromatogram method and LI-8100 automatic soil CO_2 flux system. Combined with environmental factors (included soil temperature, soil moisture, soil salinity, air temperature, relative humidity and solar radiation), the emission characteristics of soil CO_2 and the main influence factors were investigated. The results show that the alpine meadow soils were atmospheric CO_2 sources during the whole observation periods, with the soil CO_2 diurnal flux rate ranging from 2.52 to 532.81 mg·m~(-2)·h~(-1). The annual total emission of soil CO_2 was 1 429.88 g·m~(-2), with annual mean fluxes of 163.23 mg·m~(-2)·h~(-1). The soil CO_2 flux had significant correlation with air temperature and relative humidity, soil temperature, water content and salt content at the depth of 2 cm, 10 cm, 20 cm and 30 cm. The soil temperature at the depth of 2 cm, air temperature, solar radiation and soil salt content at the depth of 2 cm were the most important influence factors for soil CO_2 flux during the completely thawed period, freezing process, completely frozen period and thawing processes, respectively. The 72.0%, 82.0% and 38.0% changes of soil CO_2 flux variation can be explained with the best fitting temperature factor variation in the completely thawed period, freezing process and whole observation period, corresponding to 1.93, 6.62 and 2.09 of Q_(10) value, respectively. The results also show that the cumulative soil CO_2 flux during freezing-thawing periods (including thawing and freezing periods) and completely frozen period accounts for 15.35% and 11.04% of the annual total emission, which should not be neglected in estimation of the soil CO_2 flux in the alpine meadow of permafrost regions in the Tibetan Plateau.