Calix[4]crown-6-2,4-bis(2-hydroxyethyl ether) (2), which has crown-6 moieties at the 1- and 3-positions and hydroxyethyl functions at the 2- and 4-positions, was prepared for the syntheses of polyester3 and polyurethane4 by reactions with adipoyl chloride and hexamethylene diisocyanate, respectively. The ion binding characteristics of monomer2 and polymers3 and4 toward alkali and alkali earth metal ions were measured by liquid-liquid extraction from the aqueous phase into the organic phase. We observed that the polyurethane4 has a higher binding affinity toward various metal cations when compared to polyester3, which exhibits cesium ion selectivity.