【Objective】A one-year-round field experiment, monitoring nitrous oxide (N₂O) emissions during the growing seasons of four consecutive vegetable crops and yields of the crops, was conducted to investigate effects of reduced application of nitrogen (N) fertilizer andapplication ofchlorinated pyridine (CP), a kind of nitrification inhibitor, on N₂O emission and vegetable yield. 【Method】During the observation period from May, 2015 to May, 2016, four different species of vegetables were cultivated one by one, namely, amaranth, water spinach, cilantro and baby bokchoy. The experiment was designed to have two treatments in N input i.e.640 and 960 kg hm^-2a^-1,or a reduced N dose (Nr) and a normal N dose (Nn). Urea was applied as N fertilizer coupled with CP (CP-N) or without CP (N). Phosphate and potassium fertilizers wereapplied in the form of calcium/magnesium phosphate (12% P₂O₅ and potassium chloride(60% K₂O)at a rate of 960 kg hm^-2a^-1.All the fertilizers were evenly distributed among the four crops. Each treatment had three replicates. N₂O fluxes were monitored with the static-closed chamber method and gas phase chromatography. Air samples were collected normally once a week and once every two or three days during the 7 ~ 10 days after the application of N fertilizer.【Result】Results show that N₂O flux varied significantly with the season in all the treatments, showing a trend of rising higher in the period from May to September and staying lower in the rest of the year.The N₂O flux during the growing season of water spinach was the highest and reachedN 6426 μg m^-2 h^-1 soon after N fertilization, which could probably be attributed to the high temperature in the season.But no apparent peaks were observed during the growing seasons of cilantro and baby bokchoy, when the highest N₂O fluxreached N664.9and 914.9μg m^-2 h^-1 respectively. N₂O flux was found significantly and positively related to soil water content and soil temperature (p<0.05) and to N fertilizer application rate too. In treatment Nr, CP-Nr, Nn and CP-Nn, N₂O flux varied in the range of N 3.2~4280, 5.0~3293, 3.2~6427 and 1.2~6097 μg m^-2 h^-1, respectively. During all the four vegetable growing seasons, treatment Nr was always lower than treatment Nn in N₂O flux. Compared with treatment Nn, treatment Nr could reduce cumulativeN₂O emission by 27.1% on average without significantly affecting yield of the crops (p<0.05). In the treatments equal in N application rate, amendment of CP reduced cumulative N₂O flux, which indicates that CP is capable of mitigating N₂O emission in the vegetable field.During the year of the experiment, treatment Nn was found to be the highest in cumulative N₂O emission, reaching up to N59.2±4.4 kg hm^-2, while treatment CP-Nr the lowest, getting down to 31.2±2.2 kg hm ^-2. Comparison between treatments equal in N application rate, CP amendment reduced total cumulative N₂O emission by 29.4% and 26.0%, N₂O emission factor by 60.9% and 42.4%, and yield-scaledN₂O emission by 32.1% and 30.3%, respectively, in treatment CP-Nn and CP-Nr, without significantly affectingcrop yield.In the soil of the vegetable field, the content of NH₄⁺-N and NO₃⁻-N variedin the range of 10.8 ~ 803.9 and 0.9 ~ 520.0 mg kg^-1, respectively. The average NO₃⁻-N content in the soil of treatment Nr, CP-Nr, Nn and CP-Nnwas 31.6, 33.2, 35.7 and 43.3 mg kg^-1, respectively, and the average NH₄⁺-N content, 51.0, 50.9, 53.8 and 60.4 mg kg^-1, respectively. Obviously, with rising N application rate, the content of inorganic N gradually increases in all the treatments. 【Conclusion】Taking into account cumulative N₂O emission, N₂O emission factor, yield and yield-scaled N₂O emission, Treatment CP-Nr is capable of reducing N₂O emission and getting high vegetable yields simultaneously. Hence, the practice of reducing N fertilizer application rate by one third coupled with CP amendment can be used as an effective vegetable field management measure in intensive vegetable production to mitigate N₂O emission and maintain crop yield.