Abstract: An ignition device for an internal combustion engine which comprises a DC-DC converter for stepping up battery voltage; a capacitor charged with output from said DC-DC converter; an SCR for discharging the electric energy stored in the capacitor through the primary side of an ignition coil; a circuit for igniting the SCR according to the operating condition of a contact breaker; a bias voltage source for rectifying output voltage from bias voltage generating winding fitted to the oscillation voltage stepup transformer of the DC-DC converter and impressing the resultant negative output on the SCR gate and the resultant positive output of the SCR cathode; a transformer type coupling circuit connected between a circuit included in the DC-DC converter to generate high rectified output voltage and the capacitor, thereby coupling the DC-DC converter with the capacitor, wherein the transformer type coupling circuit prevents excess load from being applied on the DC-DC converter when the SCR is rendered conducting and