PURPOSE: To efficiently produce a high quality metal carrier excellent in durability by adhering a joining preventing agent to the prescribed place of flat sheet and executing diffusion joining the prescribed place of the contact part between a corrugated sheet and flat sheet.

CONSTITUTION: For joining prevention, non-joining part is stably obtained better through the method to coat on a wide region of a flat sheet 1 than one to coat on a narrow region of the top part of a corrugated sheet 4. In the case the corrugated sheet 4 is shifted relative to the flat sheet 1, because a joining preventing agent 2 is coated on the flat sheet 1a, the joining preventing agent constantly exists in more than fixed amount corrugated on the top of corrugated sheet 4. The method to adhere the joining preventing agent 2 on the the prescribed place of flat sheet 1, for example, prior to constructing a honeycomb body, the joining preventing agent 2 is adhered on the prescribed place of flat sheet 1 by a coating roll 3. 4 adhesion place of joining preventing agent 2 is arbitrarily selected by adjusting a width of the coating roll 3 and a contact length with the coating roll 3 while traveling the flat sheet 1 in the longitudinal direction.