To obtain graphite/copper composites with excellent microstructures, preparation process including mechanical milling, compact compressing, vacuum hot pressed sintering and hot extrusion had been put forward. Effect of milling time and hot extrusion on microstructures of composites had been analyzed and investigated by optical microscope. The results show that after mechanical milling, refined and uniform distributed graphite phase could optimize microstructures of composites. While increasing extrusion ratio, graphite particles and graphite fibers in longitudinal cross-section of composites could be refined effectively. Under of the same conditions, grain size of copper in graphite/copper composites is larger when raising extrusion temperature.