The interfacial characteristics of Ti/TiAl, Nb/TiAl and NbTi/TiAl composites were studied by using the simulated specimens. The results showed that the interfacial reaction layer of the explosion specimen was thicker than that of the HIP's specimen, and there are obvious differences in the interfacial characteristics for these three HIP's specimens under the same condition. The HIP's Ti/TiAl and NbTi/TiAl specimens had thicker interfacial reaction layers and higher interfacial bonding strength than the HIP's specimen.