Methane from rice field contributes an importment part to the atmospheric methane. In paddies methane is produces in anaerobic condition.After three year' s study of methane emission from rice paddies in Hangzhou China, we found the diurnal and seasonal variations of methane emission rate more complex than other scientists reported before. Seasonal variation was influenced by rice growing activities and weather conditions (e. g. pulm rain rain season in the lower reaches of Changjiang river).Fertilizer treatment did not show siginificant influence on methane emission which may be due to the rich content of organic matters in the soil.