Packed soil-core incubation experiments were done to study the effects of carbon (glucose, 6.4 g C m^-2) and nitrogen (NH₄Cl and KNO₃, 4.5 g N m^-2) addition on nitrous oxide (N₂O) and carbon dioxide (CO₂) fluxes during thawing of frozen soils under two forest stands (broadleaf and Korean pine mixed forest and white birch forest) with two moisture levels (55 and 80% water-filled pore space). With increasing soil moisture, the magnitude and longevity of the flush N₂O flux from forest soils was enhanced during the early period of thawing, which was accompanied by great NO₃-N consumption. Without N addition, the glucose-induced cumulative CO₂ fluxes ranged from 9.61 to 13.49 g CO₂-C m^-2, which was larger than the dose of carbon added as glucose. The single addition of glucose increased microbial biomass carbon but slightly affected soil dissolved organic carbon pool. Thus, the extra carbon released upon addition of glucose can result from the decomposition of soil native organic carbon. The glucose-induced N₂O and CO₂ fluxes were both significantly correlated to the glucose-induced total N and dissolved organic carbon pools and influenced singly and interactively by soil moisture and KNO₃ addition. The interactive effects of glucose and nitrogen inputs on N₂O and CO₂ fluxes from forest soils after frost depended on N sources, soil moisture, and vegetation types.