The title complex has been obtained from a reaction between Ru3(CO)10(PMe2Ph)2 and C2(CO2Me)2. The alkyne is attached to the closed triangular Ru3 cluster in the usual mu-3-eta-2-parallel-to mode, the two Ru atoms to which the alkyne is sigma-bonded also bearing the PMe2Ph ligands, and being bridged by a CO group. A minor product also isolated from this reaction was partially characterised as Ru3{C2(CO2Me)2}3(CO)6-(PMe2Ph)2.