A dye fixing agent for water-color ink to be contained in the water-color ink accepting layer of an ink jet recording medium having an water-color ink accepting layer formed on a substrate, which is a hydrotalcite compound containing a silicic acid anion and a sulfuric acid ion, or a silicic acid anion as an anion(s). An ink jet recording medium comprising the dye fixing agent for water-color ink formed on a substrate. The dye fixing agent for water-color ink of the present invention is excellent in the fixability of water-color ink, the resolution of an image recorded on a medium, water resistance and light resistance.