An ignition coil for an internal combustion engine with a compact height and width includes an actuated magnetic portion of an iron core around which a primary coil is wound having an axis line crossing an ignition plug axis line of the internal combustion engine at a right angle; and a switching unit which is disposed at an end of the actuated magnetic portion vertically to the axis line of the actuated magnetic portion and intercepts a primary current flowing through the primary coil. This ignition coil can be manufactured at a greatly reduced cost, compared to the conventional ignition coil in which only one of the height or width is made compact, by reducing the required size of the press mold for the case and by reducing the initial investment for the equipment.