To provide a manufacturing method for an ink jet medium to be recorded by means of ink, which has high ink absorbing properties and excellent image color properties.

The ink jet medium to be recorded has a porous layer constituted by applying a coating composition, containing a hydrophilic polymer and inorganic ultrafine particles, onto a substrate. The manufacturing method for the ink jet medium to be recorded is characterized in that an acidic substance is added to the coating composition immediately before application of the coating composition onto the substrate so as to bring about gelation on the substrate. Preferably, the hydrophilic polymer is taken as silanol denatured polyvinyl alcohol. Preferably, the inorganic ultrafine particle is taken as a synthetic silica fine particle whose primary particle diameter is in a range of 3-100 nm. More preferably, the inorganic ultrafine particle is taken particularly as a gas phase process silica fine particle or colloidal silica. Preferably, the substrate is taken as resin coating paper on which a coating layer of a thermoplastic resin is provided.