A method for forming an end plate for a heat exchanger and a heat exchanger formed by this method are provided. The endplate is formed by preparing a concave die including a groove bottom surface and a pair of groove wall surfaces extending from both ends in the width direction of the groove bottom surface; preparing a convex die including a convex top surface facing the groove bottom surface of the concave die, convex wall surfaces facing the groove wall surfaces of the concave die, and protrusions provided along both sides in the width direction of the convex top surface; and inserting a plate member between the concave die and the convex die.
