Soil fauna e.g. nematode and earthworm, occur commonly in agricultural soil, may affect the greenhouse gas fluxes by both direct and indirect effects on organic-matter decomposition, nutrient cycling and the diversity and structure of microbiota in soil. We prepared soil with greater populations of bacterial-feeding nematodes, compared to a nematode-killed soil, to determine the effects of bacterial- feeding nematodes and earthworms on greenhouse gases emissions. Laboratory incubations were carried out for a period of 15 days. Carbon dioxide and nitrous oxide concentration were simultaneously analyzed with a modified gas chromatograph equipped with two detectors of FID and ECD. Soil with greater population nematodes and earthworms enhanced CO2 and N2O emissions. Cumulative emissions of the two gas fluxes in the greater population nematodes treatment and the greater population nematodes with earthworms treatment increased by 4.3 times and 5.2 times for CO2, 1.8 times and 2.7 times for N2O, respectively versus the nematode-killed treatment. The emission fluxes of CO2 and N2O in soil with greater nematode populations were 19% and 21% higher than that of soil with smaller population of nematodes, inoculation of earthworms in greater population nematodes resulted in 12% and 27% more emission of CO2 and N2O than earthworms in smaller population nematodes. There are significant differences between each treatment except in soil with smaller population nematodes inoculated earthworms and soil with greater populations of nematodes. The two gas fluxes were significantly correlated (R2=0.9414; p<0.01). The greater population nematodes increased DOC value when compared with the smaller populations nematodes. Cumulative emissions of CO2 and N2O from the soils treated with different population nematodes were positively correlated with DOC concentration measured at the start of gas sampling (p < 0.05).