Herein, we present the capability of creating silicon carbide (SiC) nanowires and branched nanostructures via a released cataltic process. Core-shell structured carbon-encapsulated iron nanoparticles were used as catalysts for SiC nanostructures formations by vapor-solid reaction. Various SiC nanostructures, including SiC nanocones, biaxial SiC-SiC composite nanowires, SiC-Fe-SiC junctions, Y, T branched SiC nanowires, and other complex heterostructures were observed from this process. It was demonstrated that the encapsulated iron could gradually migrate out of the carbon shell, and the released iron nanoparticles catalyzes the SiC nanostructures formation. Their morphologies and microstructures were investigated by different techniques, including scanning electron microscopy (SEM), X-ray diffraction (XRD) and transmission electron microscopy (TEM), and their formation mechanisms are proposed.