The crystal structure of the title compound, [RhI(C(18)H(15)Sb)(3)(CO)], represents a rare example of a crystallographically characterized five-coordinate Rh(I)-SbPh(3) complex. The compound crystallizes with the I-Rh-CO core on a threefold rotation axis, with three crystallographically equivalent triphenylstibine ligands. Selected geometric parameters are: Rh-I = 2.7159 (8), Rh-Sb = 2.5962 (4), Rh-C(CO) = 1.825 (6) and C(CO)-O 1.153 (6) A, and Sb-Rh-I = 89.374 (10) and Sb-Rh-C(CO) = 90.626 (10) degrees. The cone angle of the SbPh(3) ligand was determined as 137 degrees, according to the Tolman model.