Abstract: The microstructure evolution and characteristics of Fe fibers of in situ deformed Cu-14.5%Fe composites were investigated. The results showed that the disordered Fe dendrites formed in solidification process of Cu-Fe alloys are rearranged along the drawing direction with the increasing deformation due to drawing and present the ribbon-like morphology on the transverse section. This is because of the texture orientation of the two different phases during large deformation. Based on the quantitative metallographic analysis, a relationship between interfiber spacing d and the drawing ratio η is given, i.e., d=41.76exp(-0.411η). Moreover, the relationships between the fiber thickness (δFe) and fiber width (bFe) and the drawing ratio can be expressed as ln(δFe)=3.396-0.686η and ln(bFe)=4.114-0.431η, respectively.