The effects of Pure Al/Pure Fe and Al + 0.88Si/Fe + 1.48Si intermetallics on the interfacial bonding properties of Al/Fe composites were studied. The results showed that: When there was no Si addition, IMC was just formed, when the thickness was between 200 nm and 500 nm, there was no crack in the interface and the bonding strength was high. With the increase of IMC thickness, discontinuous compounds began to form on the interface, crack appeared on the Al side of the interface, the bonding strength decreased slightly. With the extension of heat treatment time, IMC became continuous distribution, the crack length and width increased obviously, the interfacial bonding strength decreased significantly. After the addition of Si, the IMC was mainly discontinuous, and the interface did not form crack. Under the similar IMC thickness, the interface bonding strength was much higher than that of the composites without Si.