The Cu-Fe permanent magnet were prepared in situ process, which has economic and mass productive merits in producing multifilamentary composites. The purpose of this research was to study the effect of reduction ratio and heat treatment on magnetic property. As the reduction ratio of Cu-Fe wire increased, the filament structure became finer and interfilament distances decreased and the morphology of filament cross section became ribbon shape. As Fe content increased significantly. The coercivity and squareness of Cu-55wt%Fe composite increased as a reduction ratio became higher, whereas they increased to maximum values at 0.09㎜ ø for Cu-30wt%Fe, and 0.066㎜ ø for Cu-45wt%Fe respectively, and decreased for further reduction. The magnetic properties of Cu-Fe composites can be more enhanced by intermediate heat treatment. The best magnetic properties were obtained from Cu-55 wt%Fe composite deformed to 0.054㎜ ø and annealed.