[Objective] The characteristics of nitrogen (N) transformation in degraded alpine meadows and identify the effects of meadow degradation on the gene abundance of soil nitrogen-transforming microorganisms were studied thoroughly, in order to provide a basis for understanding the degradation mechanism and scientific management of alpine meadows.[Methods] A soil survey along a degraded gradient, including undegraded, lightly degraded, moderately degraded, and severely degraded meadows, in the Qinghai-Tibetan alpine region was conducted. The changes in soil physicochemical properties and genes in N transformation (including nifH, amoA-AOA, amoA-AOB, narG, nirK, nirS, and nosZ) were investigated by using real-time quantitative PCR method, and the drivers of these functional genes were clarified.[Results] ① The contents of soil organic carbon (SOC), total N, nitrate N, and ammonium N decreased along the degradation gradient. ② Degradation led to a significant reduction in the abundance of nifH, amoA-AOA, and amoA-AOB genes, whereas it caused an increase in the abundance of narG, nirS, and nirK genes, which was the maximum in the severely degraded meadow soils. ③ The abundance of the nifH, amoA-AOA, and amoA-AOB genes was significantly positively correlated with the contents of SOC, nitrate N, ammonium N, and soil moisture. The abundance of the narG, nirS, and nirK genes was significantly negatively correlated with the contents of SOC, nitrate N, and ammonium N, whereas it was positively correlated with the pH value.[Conclusion] The degradation of the alpine meadows had an important influence on the microorganisms involved in N transformation. The SOC, pH value, and moisture were the significant drivers of the functional genes in soil nitrogen-transforming microorganisms in alpine meadow soils.