We conducted a meta-analysis of previously published empirical studies that have examined the effects of nitrogen (N) enrichment on litter decomposition. Our objective was to provide a synthesis of existing data that comprehensively and quantitatively evaluates how environmental and experimental factors interact with N additions to influence litter mass loss. Nitrogen enrichment, when averaged across all studies, had no statistically significant effect on litter decay. However, we observed significant effects of fertilization rate, site-specific ambient N-deposition level, and litter quality. Litter decomposition was inhibited by N additions when fertilization rates were 2-20 times the anthropogenic Ndeposition level, when ambient N deposition was 5-10 kg N· ha-1· yr-1, or when litter quality was low (typically high-lignin litters). Decomposition was stimulated at field sites exposed to low ambient N deposition (<5 kg N· ha-1· yr-1) and for high-quality (low-lignin) litters. Fertilizer type, litterbag mesh size, and climate did not influence the litter decay response to N additions.