Abstract:N2O emissions from paddy soils with various water contents incubated at 30 C were measured. During the 39 days' incubation, soil with water content up to its field capacity had the highest N2O emission. When soil water content was above the field capacity, dentrification was the dominant process for N2O formation. And when soil water content was below the field capacity, there was only a small amount of N2O emission, though the nitrification was most significant. In a pot experiment,N2O and CH4 fluxes from paddy soils under normal water management, continuous flooding and moist irrigation were measured over the rice-growing season. There was little N2O emission from paddy soil under continuous flooding. Unfortunately, the emission of CH4,another important greenhouse gas, dramatically increased. In contrast, there was no significant CH4 emission from paddy soil under moist irrigation whereas its N2O emission was much higher than other treatments.