PROBLEM TO BE SOLVED: To provide a manufacturing method of a catalyst carrier to prevent a wash coat solution from being excessively adhering to an inner surface of an exhaust gas passage so that no surfaces intersecting at an acute angle are present.
SOLUTION: Projections 11a, 12a projected to one side are provided on two metal flat foils 11, 12. The projections 11a, 12a are formed by punching the flat foils 11, 12 by a punch and a die, and holes 11a, 12b are simultaneously formed in the flat foils 11, 12. The flat foils 11, 12 overlap, and are spirally wound in the overlapping condition, bent tips 11d, 12d of the projections 11a, 12a are joined with the surfaces of the corresponding flat foils 11, 12 by brazing or the like to manufacture a cylindrical metal carrier. This catalyst carrier demarcates an exhaust gas passage 16 between the metal flat foil 11, 12 adjacent to each other in the radial direction with an interval (h) regulated by the projections 11a, 12a. A wash coat solution not shown in the figure is applied through immersion to the inner surface of the passage 16 and dried, and then, the catalyst is carried on the surface of this wash coat solution to form the catalyst for purifying the exhaust gas.