Greenhouse gases mainly come from farmland soils. Re-spreading chaff ( straw returning ) is an effective ecological management in China. Quantitative analysis of straw residues together with reduced fertilization rates can provide a scientific basis for reducing greenhouse gas emissions. A field experiment with six different fertilizer amounts combined with straw residues was carried out in a vegetable field ( lettuce-cabbage-chili rotation),including the control ( CK),conventional fertilizing ( F),straw returning with 100% conventional fertilizing ( 100FS),straw returning with 70% conventional fertilizing ( 70FS),straw returning with 60% conventional fertilizing ( 60FS),and straw returning with 50% conventional fertilizing ( 50FS). The dynamic characteristics and emission factors of CO_2,CH_4 and N_2 O in the soil were analyzed using an in-situ,closed chamber,gas chromatography-based system, from November 2016 to September 2017. The results showed that the emission of CO_2,CH_4 and N_2 O has seasonal variation characteristics. The peak value mainly occurred in April to August,and the gas emission peak would appear after fertilizing and irrigating. Compared with F treatment,straw returning with fertilizing treatments reduced the N_2 O emission fluxes,cumulative emission and emission factor,especially in the 100FS treatment. The N_2 O cumulative emission and emission factor was 60.76 kg·hm~(- 2),0.138 kg·kg~(- 1) ( N_2 O-N/N) respectively in 100FS treatment during planting chili was more than that during planting lettuce and cabbage. Moreover,straw returning with reducing conventional fertilizing could reduce the N_2 O emission factor compared with 100FS treatment. The CO_2 emission fluxes 55.28-1 831.62 [mg·( m~2·h)~(- 1)] and cumulative emission ( 7 502.13-25 988.55 kg·hm~(- 2) ) in 70FS treatment were lower than that in CK and F treatments,while other treatments increased the CO_2 emission fluxes and cumulative emission,especially in 60FS and 50FS treatments. During planting lettuce and cabbage,the CH_4 cumulative emission mainly showed negative values in treatments except for CK,indicating that soil could adsorb CH_4. Moreover,straw returning with 30%-50% conventional fertilizing treatment could reduce CH_4 emission fluxes and cumulative emission during planting chili,but increased in 100FS. Compared with CK and F treatment,generally,straw retuning with conventional fertilizing could significantly increase the global warming potential ( GWP) in the study,except for 70FS treatment. 70FS could reduce the CO_2,CH_4 emission and the GWP of greenhouse gases,but could not significantly affect N_2 O emission reduction.