Over 1 year we followed the seasonal variations of N₂O and CH₄ fluxes at a tropical rain forest site in Australia. In addition, meteorological parameters, litter fall and decomposition, plant species composition, and concentrations of NH₄⁺/NO₃⁻ in the soil and N₂O and CH₄ in the soil atmosphere were measured. N₂O emissions showed a pronounced seasonal pattern with highest rates in the wet season (108.6 μg N m⁻² h⁻¹) and significantly lower rates during dry season (mostly <10 μg N₂O-N m⁻² h⁻¹). N₂O emissions were positively correlated to N₂O-concentrations in the soil profile and to moisture, but not to concentrations of NH₄⁺ and NO₃⁻. The annual emission of N₂O (N = 6015) was 0.97 kg N ha⁻¹ yr⁻¹, and, thus, approximately 7 times lower than a previous estimate for the year 2000. The marked differences in N₂O emissions between different years indicate that the interannual variability of N₂O emissions from rain forest soils cannot be neglected. With regard to CH₄ the soil functioned throughout the entire year as a significant sink. Rates of CH₄ uptake during the dry period (35–68 μg CH₄ m⁻² h⁻¹) were higher as compared to the wet period (4–45 μg CH₄ m⁻² h⁻¹). A close linear correlation between soil moisture and magnitude of CH₄ uptake was found. The calculated annual CH₄ uptake (N = 6090) is 3.2 kg CH₄ ha⁻¹ yr⁻¹. This implies that tropical rain forest soils function as significant sinks for atmospheric CH₄ on a global scale.