To provide a metallic honeycomb body in which a characteristic for making' exhaust gas to a turbulent flow is excellent by alternately forming an uneven groove having desired height in the cross section at a desired interval in the longitudinal direction of a flat foil and forming an uneven row consisting of an unperforated unevenness part in the cross direction near to both sides of the uneven groove.

A recessed streak groove 1a and a projecting streak groove 1b which have desired height are alternately formed with a desired interval d1 in the direction orthogonal to the passing direction F of exhaust gas at time for being formed into a metallic honeycomb body. Furthermore, uneven rows consisting of arranged parts 11, 12 of an unperforative streak are alternately arranged while keeping a desired interval d2 in the view of the passing direction F of exhaust gas in the parts near to both sides of the respective recessed streak groove 1a and the projecting streak groove 1b. In such a way, when a flat foil consisting of the recessed streak groove 1a and the projecting streak groove 1b is assembled into the metallic honeycomb body, the surface area of the flat foil is increased. Further, exhaust gas flow is made uniformly and effectively into a turbulent flow by the unperforated unevenness part and contact efficiency with a carried catalyst is increased.