To enhance the positional precision when a holding mat is integrated with a ceramic catalyst carrier by automating many integration steps to improve the working efficiency.

This apparatus is provided with: a pushing-in unit 7 arranged on a vertically movable tool base 6 for pushing the ceramic catalyst carrier 14 into a concave part 3a of a forming die 3 together with the holding mat 13; first and second pressurizing means 8, 9 for pressurizing both edge parts of the holding mat 13 from the rear sides so that both edge parts of the holding mat 13 meet the upper circular-arc surface of the ceramic catalyst carrier 14; first pressurizing pieces 10, 10 and a second pressurizing piece 11 arranged respectively at the tip parts of the first and second pressurizing means and; a pushing-up means 12 for pushing upward the ceramic catalyst carrier 14 held at the bottom of a concave part 13a together with the holding mat 13.