In order to make bulk and weight of the upper igniter case division of the armor case, small, and to design center of the gravity of the total apparatus to be lower underneath so as to provide an igniter which is tough to the oscilliation, the igniter for the internal combustion engine has the armor case equipped with the coil department and igniter unit (30) therein, and said armor case has the igniter case having the coil department case (15 b) and the connector department (34), furthermore, said coil department case (15 b) mentioned above is inserted in the plug hole (5) of the internal combustion engine, and the igniter unit (30) is mounted in the igniter case, and furthermore, the igniter unit (30) mentioned above has the semiconductor device (31) of the simple substance silicon chip built-in the simple substance silicon chip mounting the semi-conductor for switching and the current limiting circuitry (31 b) therein, and the semi-conductor for switching mentioned above consists of the insulated bipolar transistor (IGBT) (31 a) or the power transistor.