An exhaust-gas purifying apparatus includes an outer cylinder, a plurality of cylinder-shaped supports, and a catalytic layer. The cylinder-shaped supports are disposed in the outer cylinder, and have an outer peripheral surface and an inner peripheral surface. At least two of the neighboring cylinder-shaped supports contact with each other with the outer peripheral surfaces. The catalytic layer is loaded on at least one of the outer peripheral surface and inner peripheral surface of the cylinder-shaped supports. At least one of the cylinder-shaped supports has a ring-shaped cross-section with a cut-off, and is disposed in the outer cylinder in such an elastically deformed state that it expands in the centrifugal direction. Thus, the exhaust-gas purifying apparatus not only shows a high exhaust-gas purifying ability, but also is good in terms of the assemblage easiness. Moreover, the exhaust-gas purifying apparatus exhibits improved misfire resistance.