In a corrugated fin which is formed and bent into a wave-form, a plurality of both-side-cut-louvers 8, which are laminated on each other and formed into a group, and one-side-cut-louvers 7, which are arranged at end portions of the group of both-side-cut-louvers 8, are formed being raised, and a cross-section in the louver laminating direction of at least one of the one-side-cut-louvers 7 is formed into a substantial V-shape. An inclined face 70 of the one-side-cut-louver 7 adjoining the both-side-cut-louver 8 is made to cross a centerline in the fin thickness direction and a length of the inclined face 70 is made to be the same as that of the inclined face of the adjoining both-side-cut-louver 8.