An ignition apparatus for internal combustion engine includes an ignition coil in which a main primary coil and an auxiliary primary coil are magnetically coupled with a secondary coil that is connected to a spark plug. In the ignition apparatus, a main ignition circuit unit controls energization of the main primary coil and performs a main ignition operation in which a spark discharge is generated in the spark plug. An energy supply circuit unit controls energization of the auxiliary primary coil and performs an energy supply operation in which a current that has the same polarity as a secondary current that flows through the secondary coil as a result of the main ignition operation is superimposed on the secondary current. The auxiliary primary coil includes a plurality of auxiliary-primary-coil portions. The energy supply circuit unit performs the energy supply operation using one or more of the plurality of auxiliary-primary-coil portions.