The rice-duck ecological system is one of the classics practices from the traditional Chinese agriculture. Study on its economic significance and nitrous oxide emission of this practice can provide theoretical and practical basis for further development and utilization of this classical agricultural technique. Nitrous oxide emission from rice-duck complex ecosystem was measured in situ by using static chambers technique, and the greenhouse effect of nitrous oxide using global warming potentials (GWPs) and its economic significance were assessed. Results were shown that nitrous oxide emission from rice-duck complex ecosystem presented distinct diurnal and seasonal variation. Diurnal variation of nitrous oxide emission was highly correlated with the activities of ducklings. The peaks of nitrous oxide emissions were normally increased in the early morning and at 16:00 due to the frequent movement of ducklings at these time period. The seasonal variation was varying, and the peak of nitrous oxide emission appeared at the ripening stage. Under the same urea application as basal fertilizers, the nitrous oxide flux from RD was higher than that from CK, and the mean emission rate was about (14946±25.81)μg·m-2·h-1 and (138.84±25.26)μg·m-2·h-1, respectively. The cost of greenhouse effect was 28314 yuan·hm-2 and 265.47yuan·hm-2, respectively. In addition to the achieved economic benefits of 7687.66yuan·hm-2, which is 1932.33 yuan·hm-2 more than those who adopted a conventional without duck technique, respectively. Rice-duck complex ecosystem is still populated by farmer with its economy benefit.