A novel macroporous silica-based supramolecular recognition compound 1,3-[(2,4-diethyl heptylethoxy)oxy]-2,4-crown-6-Calix[4]arene (Calix[4]arene-R14) polymeric composite (Calix[4] + Oct)/SiO 2-P was prepared. It was synthesized by impregnating and immobilizing a mixture of Calix[4]arene-R14 and n-octanol into the pores of the macroporous SiO 2-P particles. The adsorption of Cs(I) and some typical fission and non-fission products (FPs) contained in high level liquid waste (HLLW) such as Na(I), K(I), Cs(I), Rb(I), Sr(II), and Ba(II) onto (Calix[4] + Oct)/SiO 2-P was investigated by examining the influence of contact time and the HNO 3 concentration at 298 K. It was found that with an increase in the concentration of HNO 3, the adsorption of Cs(I) onto (Calix[4] + Oct)/SiO 2-P increased from 0.324 M to 4.0 M HNO 3 and then decreased to 7.0 M HNO 3. At the optimum HNO 3 concentration of 4.0 M HNO 3, (Calix[4] + Oct)/SiO 2-P showed excellent adsorption ability and high selectivity for Cs(I) over all of the tested elements except Rb(I). The chromatographic separation of Cs(I) from a simulated HLLW containing ∼5.0 mM of the tested elements was performed by (Calix[4] + Oct)/SiO 2-P packed column at 298 K. Na(I), K(I), Sr(II), and Ba(II) showed no adsorption and were eluted into effluent along with 4.0 M HNO 3. Cs(I) and Rb(I) adsorbed by (Calix[4] + Oct)/SiO 2-P could be effectively eluted with water and separated from the others. It is demonstrated that (Calix[4] + Oct)/SiO 2-P is promising to apply in the separation of Cs(I), one of the heat emitting nuclides, from an acidic HLLW by extraction chromatography.