Abstract <p>Soil respiration is an important link in the carbon exchange between the soil and the atmosphere, and its dynamic changes directly affect the global carbon cycling process. Nitrogen (N) addition leads to significant changes in soil respiration in degraded alpine grasslands. However, previous research on the effects of N addition on soil respiration in degraded alpine grasslands has mainly been conducted in flatlands, with limited research on degraded sloping alpine grasslands. We attempted to remedy this deficiency by focusing on both gentle and steep slopes in the Yellow River source area of the Qinghai-Tibet Plateau to assess the effect of N fertilizer addition on soil respiration at three levels (2, 5, and 10 g m^–2 a^–1). The results showed that different slopes had significant differences in soil water content, soil temperature, and soil respiration rate (<i>P</i> &lt; 0.05). N addition on the same slope did not result in significant changes in soil temperature or water content, but significantly affected soil respiration rate on the gentle slope, and soil respiration rate decreased significantly (<i>P</i> &lt; 0.05) at a higher N dosage. However, such a relationship was non-existent on the steep slope. Soil respiration was positively correlated with soil temperature and linearly correlated with soil water content. In addition, it was also positively correlated with below-ground biomass. However, there was no significant linear relationship between soil organic carbon, total N, and total phosphorus and soil respiration. The inhibiting effect of exogenous N addition on soil respiration depends on slope, and a gentle slope will reduce the soil respiration rate of degraded alpine grasslands.</p>