Abstract: Superplastic forming and diffusion bonding (SPF/DB) of Al-6Mg alloy has been investigated in this paper. Experimetal results show that the SPF/DB of aluminium alloy can be successfully realized if the grains of the alloy have been refined and the oxide film on the surface of the aluminium alloy can be effectively removed by chemical method. The elemental diffusion behaviour at the interface of the DB joints has been analyzed by EPMA. Moreover, the relationships between SPF and DB have been initially analyzed.