Global warming is well-known, which is mainly because of the increase of greenhouse gas in the atmosphere, such as carbon dioxide (CO_2) and methane (CH_4). Natural peatland as a sink of atmospheric CO_2 and a source of atmospheric CH_4, plays an important role in global carbon cycle. However, grazing could affect the emissions of the CO_2 and CH_4 fluxes in the peatland. So far, many studies focused on the influences of grazing on the emissions of both CO_2 and CH_4 fluxes in the wetlands and there are still no consensus achieved. In this study, to understand the influence of grazing on the emissions of both CO_2 and CH_4 fluxes in wetland, we investigated the emissions of both CO_2 and CH_4 fluxes from the fencing and grazing sites in the Zoige Plateau wetland, which is the highest Plateau wetland in the world. The CO_2 and CH_4 fluxes were measured based on the dark static chamber method using the Fast Greenhouse Gas Analyzer over the growing season in 2013. Results showed that the aboveground biomass in the grazing site decreased by 350.21 g·m~(-2) compared with the fencing site, while belowground biomass in the grazing site increased by 729.17 g·m~(-2) compared with the fencing site. The mean CO_2 emissions over the growing season in the fencing and grazing sites were (845.02559.24) (standard deviation) mg·m~(-2)·h~(-1) and (763.78534.99) mg·m~(-2)·h~(-1) with no significant difference. In addition, the mean CH_4 emissions in the fencing and grazing sites were (7.655.92) mg·m~(-2)·h~(-1) and (7.914.94) mg·m~(-2)·h~(-1) with no significant difference. However, the mean CH_4 emission during the main grazing period (from late July to September in 2013) in the grazing site significantly increased by 54.3% compared with the fencing site. During the main grazing period, the enhanced CH_4 emissions in grazing site mainly relied on vascular plants transport in the low water table, the high methanogenic activity at the high soil temperature, and the large plant biomass. Therefore, the results will help to provide basic information for the reasonable wetland management and mitigating the emissions of greenhouse gas.