The objective of this study was conducted to investigate the effects of different organic and inorganic nitrogen(N) fertilizer applications on soil carbon dioxide(CO_2)and methane(CH4)emissions of lettuce(Lactuca sativa L.)by static box-gas chromatographic method using pot experiment.Applying N as a standard,pig manure,biogas manure and pig manure composting were combined with chemical fertilizers in the same total N,phosphorus(P),potassium(K)contents. There were six treatments,including no fertilizer(CK),no N fertilizer(PK),pure inorganic fertilizer(NPK),organic and inorganic fertilizer 1(20% pig manure N+80% chemical fertilizer N,NPKM1),organic and inorganic fertilizer 2(20% biogas manure N+80% chemical fertilizer N,NPKM2),organic and inorganic fertilizer 3(20% pig manure composting N+80% chemical fertilizer N,NPKM3).Results showed that soil CH4 emission flux during lettuce growing season appeared an alternate phenomenon of source and sink for each treatment.The emission fluxes at each time fluctuated after fertilization,until the overall trend was stable.With the change of the growth period, the difference between treatments was obvious.The soil CH4 accumulation emission fluxes of lettuce were -5.90 ~ -0.42 kg·hm~(-2), ranked as CK=PK>NPK>NPKM3>NPKM1>NPKM2.Soil CO_2 emission fluxes during lettuce growing season presented a trend of rising in general,slightly influenced by fertilization.The soil CO_2 accumulation emission fluxes of lettuce were 1 506.37 ~ 2 260.58 kg·hm~(-2),in the order of NPKM3>NPKM1>NPK>NPKM2>PK>CK. The variances of CH4 and CO_2 accumulation emissions gradually increased along with the growth period.The soil global warming potential of lettuce were 1.50 ~ 2.23 t CO_2eq·hm~(-2),in the order of NPKM3>NPKM1>NPK>NPKM2>PK>CK.In conclusion,different organic and inorganic N fertilizer applications showed a CH4 sink in the vegetable soil,especially in combined application of biogas manure,but pig manure fertilization resulted in the increase of global warming potential.