Multisegmented (MS) Co/CoPt3 nanowires (NWs) have been successfully fabricated by a template-assisted pulsed electrodeposition process and the length of each Co and CoPt3 segment is controlled by the pulse durations. The MS NWs show both the characteristic surface plasmon absorption and catalytic properties of CoPt3 and the strong ferromagnetic properties of Co that are affected by the interactions between Co and CoPt3. Furthermore, the ferromagnetic, optical, and catalytic properties can be well modulated by mainly changing the length of the Co and CoPt3 segments, respectively. Such multifunction of MS nanowires can be exploited for recyclable catalysts and bioassays based on their magnetic-catalytic and magnetic-optical properties, respectively.