The invention discloses a wired secret-stealing detection method. The method comprises: carrying out signal acquisition on an active line and/or a passive conductor to obtain signals transmitted or radiated externally at the active line and/or the passive conductor; and on the basis of at least one of audio amplification and demodulation techniques, a waveform spectrum analysis technique, and an electromagnetic induction technique, analyzing an acquisition result and determining whether any secret-stealing device is installed at the active line and/or the passive conductor. Therefore, even though a secret-stealing device is installed in a hidden manner or works at a frequency band that can not be detected by a common detection device, the secret-stealing device can be detected successfully, so that the detection accuracy is improved.