A treatment system includes an energy treatment tool and a power supply device. The energy treatment tool includes respective first and second grasps configured to be coupled with one another and are capable of pivoting with respect to one another so as to grip a treatment target therebetween. A plurality of bipolar electrodes is attached to the respective first and second grasps. The plurality of bipolar electrodes receives a high-frequency current to flow through the treatment target so as to develop a first temperature distribution in the treatment target. A treatment energy source is configured to be coupled to one of the respective first and second grasps and receives electric energy to generate treatment energy different from the high-frequency current and to apply the generated treatment energy to the treatment target so as to develop a second temperature distribution in the treatment target.