Aiming at the problem that traditional integral transform is easy to produce "ripple wave" interference in cable defect location, resulting in misjudgment and missed detection, this paper proposes a cable location compensation method based on frequency domain weighting of reflection coefficient spectrum. Firstly, the cable distribution parameter model is established, and the positioning principle based on the reflection coefficient spectrum is derived. Secondly, the attenuation constant is extracted by the resonance point and the function is fitted, and then the frequency domain weighted repair compensation function is constructed to realize the exponential gain compensation in the low frequency band and the Blackman window suppression in the high frequency band, which can effectively smooth the positioning curve and suppress the boundary oscillation. The simulation and experimental results show that the proposed method can reduce the waveform complexity in both single-defect and multi-defect scenarios, significantly eliminate the "ripple wave", make the "mutation peak" of weak defects clear and distinguishable, and has high positioning accuracy and strong anti-noise performance, which can provide a reliable basis for cable condition-based maintenance.