Abstract: This paper studies the effects of different hot rolling deformation amounts and the implantation of Mn powder on the microstructure of the interfaces in Al/Mg/Al composite plate. The results indicate that the interfaces of the Al/Mg/Al composite plates is well bonded under different hot rolling deformation amounts. The thickness of the coexistence zone of Mg and Al elements at the Mg/Al interface increases with the increase of hot rolling deformation amount,and the interfacial bonding effect is also enhanced. The implanted Mn powder is also beneficial to the bonding of the Al/Mg/Al composite plate interfaces:the Mn particles are dispersedly distributed on the Mg/Al interface,which greatly increase the complexity of the interface;Mn particles increase the deformation degree of some Mg/Al interfaces and is embedded in the Mg or Al layers,which is beneficial to the interface bonding strength..