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Agricultural soil with fertilization is a main anthropogenic source for atmospheric nitrous oxide (N<sub>2</sub>O). N<sub>2</sub>O fluxes from a maize–wheat rotation field in the North China Plain (NCP) were investigated for 4 successive years using the static chamber method. The annual N<sub>2</sub>O fluxes from the control (without fertilization) and fertilization plots were 1.5 ± 0.2 and 9.4 ± 1.7 kg N ha<sup>−1</sup> yr<sup>−1</sup> in 2008–2009, 2.0 ± 0.01 and 4.0 ± 0.03 kg N ha<sup>−1</sup> yr<sup>−1</sup> in 2009–2010, 1.3 ± 0.02 and 5.0 ± 0.3 kg N ha<sup>−1</sup> yr<sup>−1</sup> in 2010–2011, and 2.7 ± 0.6 and 12.5 ± 0.1 kg N ha<sup>−1</sup> yr<sup>−1</sup> in 2011–2012, respectively. Annual direct emission factors (EF<sub><i>d</i></sub>'s) in the corresponding years were 2.4 ± 0.5%, 0.60 ± 0.01%, 1.1 ± 0.09% and 2.9 ± 0.2%, respectively. Significant linear correlation between fertilized-induced N<sub>2</sub>O emissions (<i>Y</i>, kg N ha<sup>−1</sup>) during the periods of 10 days after fertilization and rainfall intensities from 4 days before to 10 days after fertilization (<i>X</i>, mm) in the 4 years was found as <i>Y</i> = 0.048<i>X</i> − 1.1 (<i>N</i> = 4, <i>R</i><sup>2</sup> = 0.99, <i>P</i> < 0.05). Therefore, the remarkable interannual variations of N<sub>2</sub>O emissions and the EF<sub><i>d</i></sub>'s were mainly ascribed to the rainfall.