In order to monitor the N2O emissions after irrigation and organic fertilization from vegetable soil in celery growing season, and make sure effective reduction measures were put forward, an experiment with 6 treatments was done in Beijing suburbs by using static chamber measurement techniques. The impact of the -5cm), NO3--N content, NH4+-N content and N2O emissions were analyzed. It was a split block experiment with irrigation and fertilization two factors. The 6 treatments were as fellows: conventional irrigation under the condition of conventional fertilization (HN), conventional fertilization <0.01), however, had no significantly influence on celery yield, WFPS and Nmin content of soil. Compared with conventional fertilization, the treatments of conventional fertilization with 1/3 decrement and no fertilization had no significantly influence on NH4+-N content of soil, however, significantly reduced NO3--N content of soil (P<0.01) by 43.96% and 76.42%, respectively. In addition, conventional fertilization with 1/3 decrement made the cumulative N2O emissions from the soil in the whole growing season of celery, significantly reduced by 62.04%, however, had no significantly influence on celery yield. In this field experiment, conventional irrigation with 20% decrement (L) and conventional fertilization with 1/3 decrement (N3) both significantly reduced N2O emissions, and had no significantly influence on the celery yield, furthermore, the combination of the decrement of irrigation and fertilization (LN3) can reduce the production costs at the same time.reductions of irrigation and organic fertilization (biogas residue) on the water-filled pore space (WFPS, 0with 1/3 decrement (HN3) and no fertilization (HN0), and conventional irrigation with 20% decrement under the condition of conventional fertilization (LN), conventional fertilization with 1/3 decrement (LN3) and no fertilization (LN0). The results showed that, conventional irrigation with 20% decrement reduced total N2O emissions by 32.23%, significantly lower than that of conventional irrigation (P )