The present invention relates to an insulated vessel which may be produced at low cost, has superior insulating capabilities and excellent volumetric efficiency, and which may be suitably employed in a thermos, cooler, icebox, insulated cup, thermal insulated lunch box, thermal insulated electric pot, heat retaining rice cooker, refrigerator or freezer box insulating material, or as an insulating layer in a bath tub. The insulated vessel of the present invention is characterized in the formation of an insulating layer in the space interval between the inner vessel and the outer vessel of a double walled vessel which is filled with a low thermoconductive gas consisting of at least one the gases of xenon, krypton, and argon, and in the disposition of a metallic heat radiation preventing material at the insulating layer.