To provide an ignition controller for an internal combustion engine capable of suppressing the worsening of a combustion condition at multiple discharge time and obtaining output of the internal combustion engine satisfactorily.

One end of a primary side coil 10a of an ignition coil 10 provided in each cylinder is connected with a battery 12 through a power supply circuit 11, and the other end of it is grounded through IGBT 13. One end of a secondary side coil 10b of the ignition coil 10 is connected with an ignition plug 15, and the other end of it is grounded through a Zener diode 16 and resistance 17 for detecting current. In this configuration, an ignition control circuit 14 turns off the IGBT 13 after predetermined charge time elapses from the start of charging of the ignition coil 10 and turns on the IGBT 13 when secondary side current I2 detected by the resistance 17 for detecting current reaches current for maintaining discharge after discharging of the ignition coil 10 is started.

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