An easy preparation method of monolithic type hydrophilic solid phase was discussed. Newly invented functional monomer with a hydrophilic cross-linking agent was co-polymerized to realize well-controlled monolithic co-continuous structure by use of diethylene glycol as porogenic solvent. We were able to control the content of the functional monomer up to 40 vol% without loss of monolithic structure. Those prepared were utilized as affinity resins after immobilization of FK506, an immunosuppressive drug as a ligand. It was found that the affinity resins prepared were hydrophilic enough to eliminate non-specific adsorption of proteins, while two of the target proteins of FK506 tested were successfully captured.