A macrocyclic supramolecular recognition agent, 1,3-bis(1-nonyloxy)2,4-crown-6-calix[4]arene (NonCalix[4]C6), was synthesized. The extraction of Cs(I), a heat generator, and some typical fission and nonfission products, La(III), Y(III), Rb(I), Mo(VI), Zr(IV), Sr(II), Ba(II), Ru(III), Na(I), K(I), and Pd(II), with NonCalix[4]C6/1-octanol in HNO3 medium was investigated. The effects of contact time, the concentration of HNO3 in the range of (0.4 to 5.0) mol.kg(-1), and temperature were evaluated. NonCalix[4]C6 showed excellent extraction ability and high selectivity for Cs(I) over the tested metals except Rb(I), which was ascribed to the effective recognition of NonCalix[4]C6 for Cs(I). The optimum acidity in the extraction of Cs(I) was 4.0 mol.kg(-1) HNO3. The extraction property and mechanism of Cs(I) were discussed. The composition of the extracted species of Cs(I) with NonCalix[4]C6 was determined as CsNO3 center dot NonCalix[4]C6. Valuable chemical engineering parameters in the extraction of Cs(I) were obtained. It is beneficial to effectively partition Cs(I) from highly active liquid waste with the NonCalix[4]C6/1-octanol extraction system.