In a method of producing an ultra thin wall metallic tube by a cold drawing process in which a drawing machine is used, a wall thickness of the metallic tube is reduced to perform drawing while a tube-wall centerline diameter of a tube material is expanded, using a solid die which gradually increases in diameter from its engaging inlet side toward its work-ending outlet side and a plug or a tapered mandrel bar which gradually increases in diameter over a corresponding distance from the engaging inlet side of the solid die toward the work-ending outlet side of the solid die, whereby the wall thickness can dramatically be reduced.