A selective adsorption/desorption of organoiodine compounds was achieved on poly(2-methoxyethyl acrylate)-analogue microspheres, wherein the side chains in the polymers act as halogen-bonding sites. These results demonstrate that the halogen-bonding sites in the side chains exhibit adequate specific affinity for organoiodine compounds. In addition, the water-swollen pMEA-analogue microspheres (microgels) showed a thermoresponsive swelling/deswelling behavior that permitted a controlled release of the organoiodine compounds upon changing the temperature. Thus, it seems plausible that a variety of problems associated with, e.g., the recovery of rare iodine-containing compounds, such as the marine-derived iodine compounds, the delivery of iodine-containing drugs, or the removal of halogen compounds from wastewater, could be resolved by polymer microspheres that exhibit controlled halogen bonding.