An amphiphilic metallo-supramolecular poly(ethylene-co-butylene)-block-poly (ethylene oxide) diblock copolymer containing a bis(2,2':6',2"-terpyridine)ruthenium(II) complex as a supramolecular connection between the two constituting blocks was used to prepare stable aqueous micelles. The micelles were characterized by dynamic light scattering and atomic force microscopy. Individual micelles were observed together with aggregates of micelles. Only the addition of a large excess of competitive ligand caused the cleavage of the very stable ruthenium complex.