Sever plastic deformation can be successfully used to refine grain size in metals and alloys. Both work hardening and precipitation hardening are important contributors of strength of aluminum–magnesium–silicon alloys. In this study, combination of precipitation hardening and severe plastic deformation has been employed to improve mechanical properties of 6063 aluminum alloy. The results indicate that natural aging after sever plastic deformation has not changed the microstructure and mechanical properties considerably. However, artificial aging at 180°C decrease hardness of deformed material partly due to dislocation annihilation occurring in heat treatment.