Direct nitrous oxide (N₂O) emission from agricultural soils depends on several factors including the application of slurries and manures, commercial N fertilizers, availability of soil organic carbon, soil structure and pH. The purpose of the study was to compare N₂O and carbon dioxide (CO₂) fluxes from soils amended with swine slurry and fertilized with commercial N. Two soils from central Iowa, were selected for the experiment. The first soil was a loamy sand with a surface layer texture of 79.0 % sand, 13.8 % clay and 7.2 % silt containing about 1.8% of organic carbon (C) and is classified as a Storden fine-loamy, mixed, mesic Typic Udorthents, and the second, a clay loam with a texture of 25.6% sand, 37.5% clay and 36.9% silt containing 4.4% of organic C is classified as a Webster fine-loamy, mixed, mesic Typic Haplaquolls. The pots were prepared containing 12 kg of soil without vegetation and were kept at field moisture capacity and 18⁰C temperature for 8 weeks. The following treatments were applied to both soils: control (no N), commercial N fertilization as a Urea-Ammonium Nitrate solution (UAN), and swine slurry, both injected at the 5 cm depth. UAN and slurry were applied at the rate of 200 kg N/ha. Measurements were performed every day over the first two weeks and every second day over the remaining period. The cumulative emission of N₂O was 3 times higher from sandy than from clayey soil. Sandy soil N₂O emission from slurry and N fertilizer treatments were about 8 to 9 times higher than from control. For the clayey soil, N₂O emission from the N fertilizer treatment was over 2 times higher than from control and 13 times higher than control from the slurry treatment. In sandy soil there was no significant difference in cumulative N₂O emission between commercial N and slurry but in clayey soil more N₂O was emitted from slurry than from commercial N treatment. Carbon dioxide emission, similar to N₂O, was higher from sandy than from clayey soil. In both soils higher emission of CO₂ was observed from slurry treatments with no difference between control and commercial N treatment. The nitrogen losses through N₂O emission from the commercial N treatment amounted to 3.3 and 0.2 % of applied N for sandy and clayey soils, respectively. From soils treated by slurry, N losses through N₂O emission amounted to 2.7 and 1.8 % of applied N for sandy and clayey soils, respectively. Results for N₂O emissions from this trial obtained for manure on both soils and for commercial N treatment on sandy soil are higher than the present IPCC value of 1.25% N₂O-N/kg N.