Mesoscale surface deformation in polycrystalline aluminum alloys subjected to uniaxial tension is numerically investigated. Three-dimensional polycrystalline models with equiaxial and extended grains peculiar to rolling are constructed by a step-by-step packing method. Calculation results have shown that the grain structure is responsible for the mesoscale surface roughening under uniaxial tension. The roughness pattern is affected by the microstructure and loading conditions. In a specimen with equiaxial grains and in a textured material loaded across the rolling direction surface relief is very pronounced in comparison with the extended grain structure loaded along rolling direction.