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 .