Atmospheric nitrogen (N) deposition has increased dramatically since the industrial revolutiondue to human activities. In terrestrial ecosystems, excess nitrogen inputs can greatly affect soilchemical properties, plant growth, and activities of soil microbes and fauna. Millipedes canfragment and consume large quantities of litter, and they regulate nutrient cycling and affectsoil fertility through excretion of faeces. Many soil fauna graze on the faeces of millipedes as apart of the soil food web. The decomposition and stabilization of these millipede faeces areespecially important in soil carbon dynamics and nutrient cycling, and these processes relyheavily upon microbial activity. However, very few studies have investigated how microbialcommunity structure and oxidase activity of millipede faeces respond to climate change,especially N deposition. Therefore, we designed a microcosm study to investigate thisquestion, which included two treatments, N addition treatment and control (without N addition).We found that: (i) microbial community structure in millipede faeces was altered and thebiomass of fungi and actinomycetes in faecal pellets were signifificantly reduced after Naddition, but bacteria still dominated in millipede faeces after N addition, (ii) oxidase activitywas suppressed in response to N addition, and (iii) microbial community structure and oxidaseactivities were signifificantly correlated to organic carbon and dissolved total nitrogen of faeces.All these changes suggest that millipede excretion activities under nitrogen depositioncontribute to carbon stabilization and reduction in greenhouse gas emission owing to thesignifificant role of fungi and associated oxidase in carbon mineralization. It is noteworthy to paymore attention to the function of saprotrophic invertebrates in future N deposition studies.