An X-ray diagnosis system comprises an inter-capacitor terminal, a first inter-switching-element terminal, a second inter-switching-element terminal, and a third inter-switching-element terminal, wherein the first inter-switching-element terminal, the second inter-switching-element terminal, and the third inter-switching-element terminal are configured to supply three-phase alternating current power, and the inter-capacitor terminal and two of the first inter-switching-element terminal, the second inter-switching-element terminal, and the third inter-switching-element terminal are configured to supply two-phase alternating current power.