The Zoige Wetland, which is located in the northeast of the Tibetan Plateau, is a typical low latitude permanent permafrost wetland, with high altitude intensive ultraviolet radiation and high soil organic matter content. The nitrous oxide fluxes in this area are critical to global warming. The main objective of this study was to elucidate the diversity and structure of the nitrate reductase (nirK) gene denitrifier community, and to further explore the microbial mediated mechanism of N₂O release in this climatically extreme area. Based on the soil physicochemical properties and denitrifying activity (PDA) analysis, restriction fragment length polymorphism (RFLP), clone library and sequencing were further used to analyze the diversity and structure of the nirK gene in the denitrifier community. The results showed that the highest activity of PDA was detected in the Axi soil, while the lowest activity was in the Fenqu soil. The PDA was significantly and positively correlated with soil organic carbon, total nitrogen and nirK gene richness (P < 0.05). The highest and lowest Shannon-Wiener diversity indices were detected in Axi and Fenqu soils, respectively. Based on the RFLP patterns, 15 different nirK gene clones were selected for sequencing and further phylogenetic analysis. The phylogenetic analysis showed that the majority of the nirK-denitrifiers in the peat soil of the Zoige Wetland belonged to Proteobacteria, and the dominant species in the Axi soil were Alphaproteobacteria, whereas Betaproteobacteria species dominated in the Maixi soil. The dominant nirK denitrifiers remained unidentified in the Fenqu soil. Redundancy analysis (RDA) was used to explore the possible relationship between the nirK denitrifiers community and soil physicochemical parameters, and the results showed that soil available potassium and available phosphorus were the two most important factors in shaping nirK denitrifier communities. In conclusion, the current study revealed obvious denitrifying activities in the Zoige Plateau Wetland. The nirK gene denitrifying community, which plays an important role in mediating the denitrifying process, was relatively diverse and positively influenced by soil available potassium and available phosphorus.