Ion removing system

An ion removing system having an ion removing apparatus that includes a fine bubble generating part generating fine bubbles and that causes the fine bubbles to adsorb metal ions to remove the metal ions from the hard water due to supply the fine bubbles generated by the fine bubble generating part into the hard water. In addition, the ion removing system includes a primary-side flow path to supply the hard water to the ion removing apparatus, a separating apparatus that separates crystals of a metal component deposited by crystallizing the metal ions removed from the hard water by the ion removing apparatus, and a secondary-side flow path that takes out, from the separating apparatus, treated water obtained by separating the crystals. The primary-side flow path is provided with a supply-side backflow prevention mechanism.