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Aims Rhizosphere is a hotspot for soil C and N biogeochemical cycling in terrestrial ecosystems. Our understanding of interaction between C and N mineralization mainly comes from the bulk soils, yet it is unknown the interaction in the rhizosphere soils. The study aimed to identify interactions between soil C and N mineralization in paired rhizosphere soils and bulk soils. Methods We used the “soil adhering to fine roots after shaking” method to collect paired rhizosphere soils and bulk soils along an altitudinal forest gradient. Soil C mineralization rates (Cmin) and net N mineralization rates (Nmin) were determined with laboratory incubation. Results We found a strong positive relationship between Cmin and Nmin in the rhizosphere soils across sites, whereas Cmin was not correlated with Nmin in the bulk soils. Furthermore, soil properties, microbial biomass C (MBC) and extracellular enzyme activities showed substantial paths affecting Cmin and Nmin using structural equation model. The coupling of Cmin and Nmin in rhizosphere soils could be triggered by root-soil interactions, resulting in the higher level of MBC, soil total C, soil total N, extracellular enzyme activities and specific microbial community structure. By contrast, the decoupling of Cmin and Nmin in the bulk soils might be attributed to the lower level of MBC and extracellular enzyme activities. Conclusions Our results demonstrated that soil C and N mineralization coupled in the rhizosphere rather than the bulk soils. These results highlight the need to distinguish rhizosphere from bulk soils for simulating soil C and N cycling in terrestrial ecosystems.