The present study describes the synthesis of a novel extractant p-tert-butyl-calix[4]azacrown ionophore (5) and evaluation of its extraction capability toward dichromate ion from aqueous solution. At first, p-tert-butyl-calix[4]azacrown ionophore (5) has been synthesized from the condensation of p-tert-butyl-calix[4]arene diamine (3) with N-(4-formylphenyl)- aza-15-crown-5 (4). The studies regarding the removal of dichromate ion from the aqueous solutions have been carried out in the liquid-liquid extraction systems. The extraction results showed that p-tert-butyl-calix[4]azacrown derivative (5) exhibited generally higher affinity towards dichromate ion than both 3 and 4 at all studied pHs. © 2012 Springer Science+Business Media B.V.