The influence of agricultural practices on greenhouse gas (GHG) generation and emission are of interest due to their potential impact on global climate change. Agricultural soils can be source or sink of GHG depending on management practices. The objective of this study was to quantify the effects of compaction and crop rotation on CO₂, CH₄ and N₂O emission on an Alfisol in Southwest Ohio. The experimental design is a split-plot, consisting of three crops: corn, soybean and winter oat rotations as the main plots, while compaction (0, 10, 20 tons) and tillage (no till, conventional till) were applied at sub-plot level. During spring and summer daily CO₂ flux was significantly greater in corn and winter oat plots (2.25 and 2.28 g m^-2 day^-1) than soybean (1.87 g m^-2 day^-1). In addition, soybean plots oxidized CH₄ (-2.74 μg m^-2 day^-1), while corn and winter oats plots emitted CH₄ (4.02 and 3.41 μg m^-2 day^-1, respectively). Both compaction and tillage management had significant influence on daily CO₂ and CH₄ fluxes in spring and summer. Daily CO₂ flux was significantly higher in the non-compacted plots (2.23 g m^-2 day^-1) and decreased with increasing compaction level (2.08 and 1.87 g m^-2 day^-1 for 10 an 20 tons, respectively). In contrast, methane fluxes increases with increasing level of compaction (-0.39, 2.73 and 3.69 μg m^-2 day^-1 for 0, 10 and 20 tons, respectively). CO₂ fluxes were higher in CT than NT plots. Nitrous oxide fluxes were highly correlated with nitrate concentration in these soils.