In an ignition apparatus for internal combustion engine, since a current caused to flow by an induced voltage generated at both ends of a secondary winding L2 when starting conduction to a primary winding L1 is checked from the conduction by diode for prevention of a reverse current 31, a spark discharge is not generated between the electrodes 13a - 13b of the spark plug 13 when starting the conduction to a primary winding L1. After ending the spark discharge, the ionized current is generated between the electrodes of the spark plug by impressing the induced voltage (the ionized current generating voltage) created at both ends of the air-fuel mixture by a residual energy of the ignition coil 15.