A cluster mounting system is provided for supporting a plurality of transmission line or coaxial cable runs in a non-interfering manner on a microwave transmission tower. The system uses a cluster mount member comprising a single strip of metal formed in such a way as to define a plurality of substantially flat mounting surfaces adjoining each other. The mounting surfaces are angularly disposed with respect to adjoining surfaces in such a way that cable carrying hangers may be affixed to each of the surfaces without contacting each other or the cable carried therein. The ends of the cluster mount member are provided with outwardly extending arms through which the cluster mount member and the plurality of hangers and cable supported thereupon may be rigidly mounted directly onto a leg of the transmission tower or a separate support member provided on the tower. Each of the mutually adjacent, angularly disposed mounting surfaces is provided with means adapted to accommodate cable hangers of the clamping type as well as the snap-in type. The cluster mount member permits a plurality of coaxial cable runs to be suspended in a clustered manner without giving rise to significant windloading forces, is easy to install and requires minimum auxiliary installation hardware.