To provide a protecting system for communication cables for a facility machine which suppresses the flow of a large current in a shielded wire of the communication cable by a potential difference between machine bases, and prevents damages of the communication cable.

This is a communication cable protecting system 1 for facility machines which is formed by arranging a plurality of industrial machines 2a-n side by side, and performing connection among the industrial machines 2a-n by the use of communication cables 4 fitted with shielded wires. Each shielded wire 6 is grounded through a capacitor means 7a-n at each industrial machine 2a-n.