A press-formed member includes a first wall with a first thickness, a second wall with a second thickness, and a first corner portion. The first corner portion is disposed between the first and second walls, with the first corner portion having an increased thickness formed by pressure-forming such that the increased thickness of the first corner portion is larger than the first and second thicknesses of the first and second walls adjacent to the first corner portion. In a manufacturing method for the press-formed member, a preliminary body structure to be deformed is provided, and the thickness of the first corner portion of the preliminary body structure is increased by applying pressure to the preliminary body structure.