There are provided a process for producing an electrical wire molded body comprising: step I of melting and kneading a polyethylene-based resin (a), a polypropylene-based resin (b), a block copolymer (c) of an aromatic vinyl-based compound and a conjugated diene-based compound and the like, and a silane coupling agent (g), and other components, to produce a silane crosslinkable flame retardant polyolefin (A); step II of melting and kneading a polymer selected from the components (a) to (c) and a silanol condensation catalyst (i), to produce a silanol catalyst rein composition (B); and step III of mixing the components (A) and (B), melt molding the mixture on a conductor and then crosslinking the molded body in the presence of water.