A method for monitoring and early warning of cable deformation includes: installing slave stations at respective monitoring points in a cable network in accordance with an order of identification numbers of the slave stations; transmitting, through a housing, a cable length change in a form of tension to an elastic conductor when a cable is subjected to an external force; monitoring, by each of the slave stations, a change in a resistance value of the elastic conductor to indirectly monitor the cable, and sending, by one of the slave stations, an early warning signal with a corresponding one of the identification numbers to a master station when the change in the resistance value of the elastic conductor of the one of the slave stations exceeds a preset range; and receiving, by the master station, the early warning signal from the one of the slave stations via a self-organizing network.