In order to simulate the corrosion evolution process of the cable in the actual environment and explore the influence of chloride ion on the corrosion process, a cellular automaton model for simulating the electrochemical corrosion process of the cable was established based on the basic principle of metal electrochemical corrosion. The entire cable corrosion system, the key elements of which were abstracted into four cell types, was discretized into a 500×500 cell grid, and its corrosion evolution process was simulated on the mesoscopic scale by the defined local rules. The effects of corrosive solution concentration and corrosion probability on the corrosion process of steel wire were analyzed. It has been found that if the characteristic parameters of cellular automata are selected reasonably, the morphology of the crater generated by cellular automata simulation is similar to actual etch pit morphology. It has also been discovered that the pitting area and corrosion rate of the steel wire increases gradually with time. The corrosive cell with chloride ions has a significant effect on the process of cable corrosion, but that without chloride ions has little effect on the corrosion rate of the wire, which indicates that reducing the concentration of chloride ions in the surrounding environment is an effective way to mitigate cable corrosion.