The depletion of carbon (C) and nitrogen (N) in agricultural soil is a critical global issue. To overcome this issue, microbes have an important role because they control the nutrient cycles. Within the microbes, fungi can produce a rather stable C and biomass with relatively lower levels of N and phosphorus (P), compared to bacteria. We hypothesized that a fungi-dominated soil can utilize nutrients more efficiently than a bacteria-dominated soil to retain C and N in soils. Then, we conducted a CNP addition test for 6 weeks using fungi- and bacteria- dominated soils, produced using a bactericide (bronopol). The bronopol treatment suppressed the bacterial abundance, suggesting the successful production of fungi-dominated soil. The rapid increase in cumulative CO₂ emission was observed in the C amended bacteria-dominated soil, which might be ascribed to the depletion of other nutrients (N&P). Cumulative N₂O production from CN and CNP soil was higher in fungi-dominated soil than in bacteria-dominated soil, which might be due to the lack of N₂O reductase in fungi. More studies are needed to understand the status of N in the soils, the relations of added C and biomass amount, and how microbial communities respond to these treatments.