Abstract: Soil moisture variation exerts strong effects on the soil nitrogen (N) mineralization in forests, and further, affects the structure and function of forest ecosystems. By using laboratory aerobic incubation method, this paper studied the soil N mineralization (ammonification and nitrification) in the Phyllostachys edulis forest (PEF) and evergreen broadleaved forest (EBF) in a subtropical region of China under the soil moisture conditions of 15%, 30% and 45%. The soil cumulative net Nmineralization in the two forests under different soil moisture conditions could be described as N_t=N₀(1-e^-kt). The soil moisture variation had great effects on the soil N mineralization potential (N₀) in the two forests, with the maximum N₀ at 30% soil moisture content for both PEF and EBF. When the soil moisture content decreased to 15% (drought) or increased to 45% (waterlogging), the decrement of the soil N₀ in PEF was obviously smaller than that in EBF, with the N₀ only decreased by 11.7% and 10.4% in PEF, but decreased by 29.0% and 30.2% in EBF under drought and waterlogging, respectively. Soil moisture variation had little effects on the soil nitrification in PEF, but inhibited the soil nitrification in EBF, and thus, altered the soil N mineralization pattern (ammonification/mineralization) in EBF. These findings indicated that the soil N mineralization in PEF was less easily affected by the soil moisture variation than that in EBF, which provided an important reference for the potential expansion of PEF into EBF under the global water change.