The microstructure of an Al-Ti-C-Ce alloy was studied by XRD,SEM,and EDS. This mother alloy consisted of α(Al),(AlTi),(TiC),and (Ti2Al20Ce) phases,and there was a second phase of a composite structure in the alloy.The TiC phase was the primary crystal nucleus,and the (TiAl) phase was segregated on the surface of TiC phase to form a TiC-(TiAl) composite crystal nucleus. Al formed a fine TiC-(TiAl)-α(Al) primary composite crystal nucleus by a peritectic reaction.The primary composite crystal nucleus with higher energy and larger cluster size was taken as the core,and other composite crystal nuclei were segregated on its surface to form a secondary composite crystal nucleus.Next,the secondary composite crystal nucleus formed the tertiary composite crystal nucleus,and so on,to form the titanium-enriched area of composite particles.