Cu-Ti and Cu-B alloys were separately cast in vacuum arc melting furnace for alloying. These alloys were added to the copper melt of 1500K in the induction furnace and performed electromagnetic stirring at 1000rpm. The cast ingot(dia : 70mm, length : 100mm) was hot extruded with the extrusion ratio of 13:1 after heating at 1073K for 1 hour. The TiB2 precipitates were observed in the extruded materials and the mean size of TiB2 precipitates was found to be about 1.5 mum. The volume fraction of TiB2 varies due to the density difference between the TiB2 and the copper melt. With the increasing of TiB2 contents from 3 to 8 vol.%, the hardness and the tensile strength increased from 95(1) to 140Hv and from 248 to 278MPa, respectively, and the electrical conductivity decreased from 82 to 70%,IACS. However, the mean size of TiB2 particle was not increased despite increasing an annealing temperature.