Lightweight has become a highlight of automotive body structure design. The torsional stability of Aluminium is 34% improved, but 3% weight lose. In order increase portion of Aluminium applied in automotive body system, besides engine cover and front fender, small size body components of Aluminum will also be applied. Aluminum alloy with strengthen process can also be applied in local reinforcement body structure, e.g. Honeycomb shaped Aluminum Alloy reinforcing parts in side doorsill provide more collision protection of side door and reduce weight as well. In addition, automotive roof front beam structure adopted Mix material of Aluminium alloy and steel weight reduced while rigidity increased.