One-dimensional multi-segment Co-CdSe metal-semiconductor heterojunction nanowires were alternately deposited by direct current electrodeposition in a two-cell system of Co electrolyte and CdSe electrolyte using porous anodized aluminum template assisted method. The morphology, structure, magnetic and optical properties of the heterojunction nanowires were characterized by scanning electron microscopy (SEM), X-ray diffractometry (XRD), vibrating sample magnetometer (VSM), UV-visible spectrophotometer (UV-Vis) and photoluminescence spectroscopy (PL). The results show that the Co-CdSe heterojunction nanowires are well layered and exist in a face-centered cubic structure. The Co-CdSe heterojunction nanowires have the same magnetic coercivity as the elemental metal Co nanowires, and simultaneously, the heterojunction nanowires exhibit the excellent optical properties.