Abstract: Taking the mining rubber-sheathed shielded cable as an example,the distributed parameter model for AC stray current was put forward according to analysis of the mechanism of AC stray current. Moreover,this paper presen- ted the distribution law of AC stray current along the length direction of the cable,and discussed the influence of the unbalanced insulation of the cable on AC stray current through theoretical computing,simulating based on Matlab,and validating by RTDS. It has been shown by the simulation results that the AC stray current flows through the shielding layer of the cable and the metal mesh decreases first,then increases along the length direction,and can reach the mini- mum at the middle of the line. In addition,when K,the unbalance factor of the insulation resistance or distributed ca- pacitance of the cable,increases from 1. 25 to 3,the AC stray current flows through the shielding layer of the cable and the metal mesh can become 10 times larger than before at the same point of the line.