With the growth of electricity demand and the development of transmission technology, multi circuit overhead transmission lines are widely used in the power system. However, due to the parallel installation of multiple transmission lines and the coupling of spatial electromagnetic fields, the induced voltage and current generated by multiple wires on the ground wire have adverse effects on the system. This article studies the problem of ground wire induced current caused by electromagnetic induction in multi circuit overhead transmission lines, and proposes corresponding simulation modeling methods and current suppression measures. A simulation model of a multi circuit overhead transmission line was established using ATP-EMTP software, and the current distribution and electromagnetic coupling effect in the line were analyzed. The suppression effect of induced current by different grounding methods and phase sequence changes was explored. Research has found that optimizing the arrangement of power lines can effectively reduce electromagnetic coupling effects, and measures such as segmented grounding can reduce the accumulation of potential and further suppress induced currents. The research results of this article provide theoretical basis for the design and operation of multi circuit overhead transmission lines, and provide strong support for electromagnetic design and optimization of power systems.