A new electrochemical generator of ozone-dissolved water, which is comprised of an electro-conductive diamond electrode and an ion exchange membrane, was evaluated using tap water as source solution, in order to confirm general versatility. Although the current efficiency of tap water became lower than that obtained in the case of pure water, ozone-dissolved water of over 1 mg/L could be produced. The durability was found to be longer than 300 h. Disinfection power using source water containing small amounts of surfactant became 10 times larger than that of water with no surfactant. Medical tests conducted with pet animals revealed that the treatment using ozone-dissolved water was clearly effective for anti-inflammatory diseases.