In order to increase the anti-interference ability and fault location accuracy of DC resistance fault location method, the error causes of the DC resistance method using in high voltage cable jacket fault location is analyzed, the measures of reducing errors of cable jacket fault location are given. According to the principle of DC resistance method, fault location error sources are analyzed. Functional expressions of voltage measurement and current measurement as well as result of cable jacket fault location are derived. On this basis, ground stray current interference effect for voltage measurement and current measurement is analyzed, the law of propagation and combination of the cable fault location error in DC resistance method are also analyzed. An error factor of cable fault location relative to circuit components parameters, frequency of interference signal, counting time of voltage-to-frequency converter, as well as injection DC current is also analyzed. Some measures aiming at reducing errors of cable jacket fault location are proposed. Calculation results and experiment data verify the proposed measures.