The neutral triple-decker ruthenocenes and anionic ruthenocene bearing a stannole dianion were successfully synthesized by the reactions of dilithiostannoles with [Cp*RuCl](4). This is the first example of a transition-metal complex bearing a group 14 metallole dianion with mu-eta(5):eta(5) coordination mode. These complexes were fully characterized by NMR spectroscopy and single-crystal X-ray diffraction analysis. In the complexes, each of the ruthenium atoms is coordinated by the stannole ring in an eta(5)-fashion. The aromaticity of the stannole dianion moieties is retained judging from no C C bond alternation in the stannole rings. CH/pi interaction was found in the packing structure of the SiMe3 derivative, which leads to a well-ordered column-like structure. The oxidation wave of the triple-decker complex was observed at -0.43 V (vs ferrocene), which reveals that the triple-decker type heavy ruthenocene is oxidized more easily than the ferrocene. Comparison of the oxidation potential between the tripledecker complex and decamethylruthenocene (Cp*Ru-2, Cp* = eta(5)-C5Me5) reveals that a stannole ligand functions as an electron-donating ligand much stronger than the conventional electron-rich Cp* ligand.