© 2016 American Chemical Society. Two families of molybdenum carbonyl metallosurfactants, Mo(CO)5L and Mo(CO)4L2, were synthesized using the functionalized phosphines Ph2P(CH2)nSO3Na (n = 2, 6, 10) and characterized by the usual spectroscopic and spectrometric methods. The study of the supramolecular arrangements of these compounds in aqueous medium has been performed by surface tension, fluorescence, dynamic light scattering, cryo-TEM, and small-angle X-ray scattering. All data point to the formation of medium and large vesicular structures with a membrane similar to the classical lipid bilayer, but it contains organometallic fragments instead of simple hydrophobic chains. Studies of CO release with these molybdenum carbonyl metallosurfactants have shown their viability as promising CO-releasing molecules.