A Co-II L-18(6) hexameric metal organic nano capsule (MONC) has been prepared and characterized using biomimetic self -assembly as the synthetic methodology. Akin to the biological behavior of zinc -finger proteins' release, uptake, and electrophilic substitution of Zn2+ ions, the assembly of this novel MONC has been accomplished by employing three sequential processes: assembly of the framework, metal ion insertion, and metal exchange, resulting in the formation of the Co-II L-18(6) hexameric MONC. In this work, inspired by the biological behavior of metalloproteins, rational control of multiple complex supramolecular self-assembly has been achieved.