Ytterbium(III) triflate has been utilized as a mild Lewis-acid catalyst for the synthesis of various calix[4]pyrroles by the condensation of pyrrole with different ketones in ionic liquids. The calix[4]pyrroles were obtained in high yield under ecofriendly, economical, and noncorrosive conditions, and the catalyst was recovered and recycled.Key words: calix[4]pyrrole, ionic liquid, ytterbium triflate.