PURPOSE: To provide a metal carrier having a honeycomb structure in which metal fatigue and damaging due to heat never happen.

CONSTITUTION: A metal carrier 3 is provided with a honeycomb body 3 manufactured by layering flat plates and corrugated plates and installed in the middle of a gas discharging pipe 1 in an internal combustion engine and an external pipe in which the honeycomb body 3 can be set and a circular heat insulation layer 5 is installed at the position at a prescribed distance from the center axis in the exhaust gas flowing in side of the honeycomb body 3. As a result, an exhaust gas flows in the honeycomb body 3 through the gas discharging pipe 1 immediately after an internal combustion engine starts working and, though the honeycomb body 3 is heated, the heat is scarcely transmitted to the part of the circumference of the heat insulation layer 5 of the honeycomb body 3 by the heat insulation layer 5 installed at the prescribed position. Consequently, excessive temperature rise in the outer circumference of the honeycomb body 3 in exhaust gas flowing-in side can be prevented and thermal deterioration can be prevented.