An ignition device for an internal combustion engine including: a DC power source; a convertor for raising the voltage of the DC power source to a predetermined voltage; a charge storing device arranged to be charged with the output from the convertor; an ignition coil; an ignition signal generator for generating an ignition signal in synchronization with the rotation of the internal combustion engine; a switch which is switched on in response to the ignition signal generated by the ignition signal generator to discharge a charge stored in the charge storing device through the ignition coil; and a controller for stopping the operation of the convertor during a period in which the ignition signal is being transmitted from the ignition signal generator.