A quasi-optimized supramolecular octupolar ordering has been achieved in a metallodendrimer made of several ruthenium tris-bipyridine complexes displaying high nonlinear optical efficiency. This acentric organization is evidenced by Harmonic Light scattering at 1.9μm, where a coherent second harmonic emission from each dendrimer unit is compared to the fully incoherent harmonic signal from a disordered linear polymer containing the same nonlinear complexes. These results show the interest of a controlled coordination strategy to build supramolecules and dendritic structures, with promising perspectives towards nanoscale applications in photonics.