Ion cyclotron range of frequencies (ICRF) heating is one of the plasma heating methods using electromagnetic wave. ICRF wave is transmitted from an oscillator to an antenna. Normally, the reflection into the oscillator side is small, however, it increases with the abrupt change of the plasma. The reflection should be decreased for the power injection without power loss, and for the protection of the oscillator. One of the methods for the reduction of the reflection is ‘conjugate-T’. We will verify that the reflection reduces with this power trasmission method.