The microstructure evolution and hardening behavior under severe plastic deformation have been studied for a 2024 aluminum alloy heat treated at different conditions. Though solid solution state specimen shows lower value of micro Vickers hardness than the peak aged and higher value than the over aged, it exhibited the biggest deformation difficulties and brought immediately the largest strain hardening effects. Transmission electron microscope observation shows that grains were refined to around 0.2similar to0.35 mum after equal channel angular pressing. In this study, the heat treatment conditions are considered to get the optimum mechanical properties.