The research thesis is based on the study of Kaohsiung MRT Orange Line. On condition that bilateral power is supplied during the target year, make two-minute interval as the background simulation, and use MATLAB & Simulink software for analysis tools. Through the establishment of the equivalent in the stray current model, discuss the original ground construction of Kaohsiung MRT Orange Line, and change the resistance of the track structure, in order to analyze whether that affects stray currents. Besides, simulate the maximum stray current density and its length in each station. To study cathode corrosion of underground metal pipeline due to stray current, the equivalent circuit model is applied for computer simulation. By changing the distance between the underground metal pipelines and MRT rail tracks the voltage potential of the pipe lines introduced by the stray current of MRT system is derived. The mitigation strategy of cathode corrosion due to stray current is also proposed in the thesis.