A method of manufacturing a load beam directly improves the finishing accuracy of the surface of the load beam having a tab and/or a dimple, and the method includes a modifying process of preparing a flat plate work serving as the load beam and irradiating a part of a surface of the work where the tab and/or the dimple is formed with a laser beam, to form a modified layer in the irradiated part and a forming process of carrying out plastic working on the part where the modifies layer is present, to form the tab and/or the dimple in the part where the modified layer is present.