Background and AimsExtracellular enzymes produced during litter decomposition play central roles in microbial nutrient acquisition and substrate decomposition. However, the regulatory effects of nitrogen (N) addition and litter quality on enzyme dynamics remain insufficiently understood.MethodsA two-year decomposition experiment was conducted in a semi-arid grassland using low-N and high-N litter (originating from N-added plots), placed under both ambient and N-added conditions. We tracked the activities of C-, N-, and P-acquiring hydrolases and oxidative enzymes, as well as microbial community dynamics, during decomposition.ResultsThe ratio of oxidative to hydrolytic enzyme activity increased with litter mass loss and acid-unhydrolyzable residue content, suggesting microbial communities adjust enzyme production to substrate recalcitrance, thus facilitating coordinated decomposition of litter components. Ecoenzymatic analysis further indicated that N inputs and litter chemistry jointly shaped microbial nutrient limitation. Specifically, N addition alleviated N limitation, whereas microbial activity under high-N litter indicated persistent P limitation. Neither microbial diversity nor life-history strategies exhibited significant responses to N addition or litter quality, yet microbial community composition and enzymatic profiles shifted significantly.ConclusionOur findings suggest that, during the two-year decomposition, microbial communities coordinated enzyme allocation according to the content of recalcitrant components, thereby facilitating the relatively synchronous breakdown of different litter components. Additionally, ecoenzymatic stoichiometry revealed that microbial communities in high-N litter face sustained P limitation. These findings reveal microbial strategies involved in decomposition and highlight their sensitivity to nutrient changes under global change.