In order to clarify the effects of water saving，nitrogen reduction，high efficiency fertilizer and straw returning on N2O emission between rice varieties and their driving factors，a field experiment was carried out in 2020 to monitor N2O fluxes during the growth period of double cropping rice，and to analyze yield-scaled N2O emission and the main driving factors related to N2O emission. Split plot design was adopted in the experiment with 8 treatments. The main plot consisted of four water and fertilizer treatments:urea 100% + intermittent irrigation(U)，urea 80% + straw returning + intermittent irrigation(US+S)，controlled release urea 80% + straw returning + intermittent irrigation(CRUS+S)，urea 80%+ straw returning + water-saving irrigation(US+S+SWD). The sub-plot factors were conventional rice and hybrid rice. The results showed that irrigation，carbon and nitrogen inputs，and plant nitrogen uptake were the leading factors regulating N2O emission from rice fields，which could explain 99% of N2O emission variations. Nitrogen input promoted N2O emission，while irrigation，carbon inputs and nitrogen uptake had a negative effect on N2O emission. Straw returning could supplement the reduced nutrients of 20% nitrogen fertilizer. Straw returning combined with conventional or controlled-release urea reduced N2O emission by 14.4%-49.4%. However，CRUS+S treatment promoted N2O emission compared with US+S treatment，indicating that straw returning combined with controlled-release urea could not achieve N2O reduction in rice cultivation. Water-saving irrigation after straw returning to the field further promoted N2O emission. Compared with US+S treatment，US+S+SWD treatment significantly increased N2O emission of double cropping rice by 114.8%-186.4%，and the increase rate of conventional rice was higher than that of hybrid rice. There was no significant difference in yield among different treatments，and nitrogen reduction and water-saving irrigation could guarantee a stable yield. However，yield-scaled N2O intensity of US+S+SWD treatment was significantly higher than that of other treatments. In general，straw returning combined with 20% reduction in nitrogen can reduce N2O emissions from paddy fields，but can not offset the increase of N2O caused by water-saving irrigation. Rational use of straw resources and reduction of nitrogen fertilizer application in rice production can help reduce N2O emission and ensure stable yield.