Aims <p>Nitrogen (N) deposition has a substantial influence on litter decay. In terrestrial ecosystems, however, its comprehensive effects on litter decay rate remain to be fully elucidated.</p> Methods <p>By reference to 52 published studies offering 542 observations, litter quality, N addition, and their combination were evaluated for their effects on decay rate in a meta-analysis using three types of decay experiments: control litter on N plots, N litter on control plots, and in situ litter.</p> Results <p>At the average level involving all studies, N addition did not significantly affect litter decay rate. Regarding the N litter on control plots, however, N addition raised the litter decay rate, and did not significantly affect it for the control litter on N plots and in situ litter. Experimental factors (N addition duration, amount and form, litterbag size, and litter style) together with environmental factors (e.g., average annual temperature and average annual precipitation) also regulated the impact of N addition on litter decay rate. Addition of N improved litter quality (increased N and phosphorus, and decreased carbon:N ratio), which, for the N litter in control plots, raised the litter decay rate. For in situ litter, although N addition improved litter quality, it did not significantly affect litter decay rate by integrated litter quality and soil conditions.</p> Conclusions <p>The N addition litter decay rate was generally elevated in Chinese grasslands, but with direction and degree affected by experimental and environmental factors.</p>