Ion beam treatment consists of a device and form of medical treatment. The device is a comprehensive system that consists of an irradiation system, a treatment planning system and a treatment verification system. The medical system consists of treatment criteria and a clinical path including daily treatment and care for patients. On April 1, 2001, HIBMC was opened as the world's first facility to provide both proton and carbon-ion radiotherapy. We have treated more than 1,300 patients with a variety of malignant tumors including those of the skull base, head and neck, lung, liver and prostate. Excellent local control for these tumors has been obtained with minimum side effects. During the clinical trials and general practice, many tumors including radio-resistant tumors were treated with proton or carbon-ion. This autumn we will start the prospective randomized trial of two beams and we will analyze the difference between them. In future we would like to start new combination treatment with both beams.