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To address the global environmental and resource crisis, integrated, efficient, and sustainable agricultural practices need to be developed. We examined the effects of combining one of two irrigation methods ( i.e. , controlled irrigation and conventional flooding irrigation) with one of four different levels of nitrogen fertilizer applications (N; 300 (N0), 270 (N1), 240 (N2), and 180 kg N ha −1 (N3)) on grain yield, water use efficiency, and N production efficiency in rice. Additionally, we analyzed nitrogen leaching at different soil depths (20 cm and 80 cm) using lysimeters and N 2 O emission using a polyvinyl chloride chamber for each of the combinations examined. We found that the irrigation regime and level of N application significantly affected rice yield, and the rice yield in the controlled irrigation treatment was higher than that in the conventional flooding irrigation treatment by 2.12%–12.30%. Of all the treatments, combining controlled irrigation with the N1 fertilizer application resulted in the greatest grain yield. Loss of N was mainly caused by nitrate leaching. Controlled irrigation and reducing the amount of N fertilizer applied in the soil reduced N leaching, and increased the N production efficiency, while increasing N 2 O emission. Furthermore, water use efficiency was increased under controlled irrigation conditions, but reduced when less N fertilizer was applied. Thus, an agricultural regime that uses less water and lower amounts of N fertilizer than are currently being used in standard practices would likely increase yield and N production efficiency in soils, while reducing potential N leaching; however, the N 2 O emissions would also increase. [ABSTRACT FROM AUTHOR]