Thin tissues (or called webs) of short aramid fibers were added at the adhesive joints between carbon-fiber face sheets and aluminum-foam core to form aramid-fiber 'composite adhesive joints' for improving the interfacial bonding strength of sandwich structures and therefore other structural properties. In-plane critical compression loads and failure modes of carbon-fiber aluminum-foam sandwich beams with short aramid-fiber composite adhesive joints are investigated and discussed in this study. Improvements in critical compression loads were achieved for all specimens with aramid-fiber composite adhesive joints of different densities. It is suggested that the composite adhesive joints using low-density short aramid fibers is effective in promoting reinforcements against cracking and delamination at the interface between carbon-fiber face sheets and aluminum-foam core. The underlying interfacial strengthening and toughening mechanisms were discussed and analyzed based on observations from optical image and scanning electron microscopy.