To provide a polyurethane elastic yarn that is superior in unwinding properties and adhesive properties in respect to a hot melt adhesive agent, and to provide a manufacturing method thereof. A polyurethane elastic yarn wherein the main structural component of the polyurethane is a polymer diol or diisocyanate; and includes a polymer that includes, as the main structural unit, a structural unit that uses an aromatic olefin and/or an aliphatic diolefin as a monomer, and is partially hydrogenated or completely hydrogenated.