Produce titanium-group metal micro-dispersion water that contains ion vapor of titanium-group metal in micro-dispersed state and that can be used as a material for health products, medical products, cosmetics, etc., by using an apparatus comprising a water tank, a high-voltage discharge generator equipped with a titanium-group metal electrode and its counter electrode, a water inlet, an outlet for produced water, and a titanium-group metal electrode feeder, in a manner causing plasma discharge in water between the titanium-group metal electrode and its counter electrode.