In the title triangulo-triruthenium compound, [Ru(3)(C(25)H(22)As(2))(C(36)H(27)As)(CO)(9)], the bis-(diphenyl-arsan-yl)methane ligand bridges an Ru-Ru bond and the monodentate arsine ligand bonds to the third Ru atom. Both arsine ligands are equatorial with respect to the Ru(3) triangle. In addition, each Ru atom carries one equatorial and two axial terminal carbonyl ligands. The phenyl rings of biphenyl are twisted from each other by dihedral angles of 50.5 (2), 44.5 (2) and 27.8 (2)°. The arsine-substituted phenyl rings make dihedral angles of 61.56 (18), 89.36 (18) and 83.27 (18)° with each other. The dihedral angles between the two benzene rings are 87.5 (2) and 81.95 (19)° for the two diphenyl-arsanyl groups. In the crystal, mol-ecules are linked into dimers by inter-molecular C-H⋯O hydrogen bonds. Weak inter-molecular C-H⋯π and π-π [centroid-centroid distance = 3.601 (3) Å] inter-actions stabilize the crystal structure.