The present invention provides an insulated coated wire comprising a wire, a wire coating layer disposed around the wire, and a wire adhesive layer disposed around the wire coating layer, wherein the wire coating layer is of one type of or a combination of two or more types of a fluorine resin, a polyamide-imide resin and a low dielectric polyimide resin having a relative permittivity of less than 3.6 at 10 GHz, and a multi-wire wiring board using the insulated coated wire.