To provide an ignition device for a capacitor discharge type internal combustion engine, for charging an igniting capacitor with a DC-DC converter as a power source without inducing spikelike high voltage in the primary coil of an ignition coil, and performing an AC discharge at the time of ignition action.

In this ignition device for a capacitor discharge type internal combustion engine, diodes 7, for constituting an AC discharge circuit, are connected to both the ends of a thyristor 5, for discharging the electric charge of an igniting capacitor 3; and an AC discharge is performed at the time of ignition action. A switch circuit 9, for constituting a damper circuit, is provided which is constituting a damper circuit for bypassing a charging current from the primary coil 4a of an ignition coil 4 in charging the capacitor 3 by output from a DC-DC converter 2, and repealing the damper circuit to permit an AC discharge at the time of ignition action.