The deformation of closed-cell aluminum foam (CAF) in different solid–liquid–gas coexisting state was studied in thispaper. The results showed that the most suitable temperature of the CAF deformation was about 635 °C, which made theCAF have maximum deformation, but its characteristic parameters changed slightly. Moreover, the multi-grain cell wall andsmall size cell were helpful to the CAF deformation in the solid–liquid–gas coexisting state. When the CAF deformed at635 °C, the inter-granular solidification microstructure and part of the primary α-Al grain were melted into liquid. The fixedor inter-locked primary α-Al grain was released and changed into the distributed discretely near-spherical grain, making thecell wall have good thixotropy. At the same time, the gas pressure in the cell was recovered to the foaming stage, so the gaspressure could be close to the flow stress of cell wall. During the CAF deformation in the solid–liquid–gas coexisting state,the cell wall deformed in thixotropic under the supporting and coordinating of the gas pressure in the cell, meanwhile, thecell was moved following the cell wall deformation. Therefore, the CAF deformation was affected by the types of the cellwalls and the cell size.