The utility model belongs to the electric power field of overhauing relates to for a cable is distinguished and is checked device, include: emission unit, the power end of connecting cable is to waveform of input in the cable, receiving element, the wave form of cable tail end or intermediate position is received to the tail end or the intermediate position of connecting cable, the control unit connects emission unit and receiving element receive receiving element received wave form and emission unit's transmitted waveform, display element connects the control unit's output shows that receiving element received wave form and emission unit transmitted waveform, the power, for cable is distinguished and is checked device provides the power. The utility model discloses a signal injection ofspecific wave form with draw, confirm target cable, make things convenient for constructor to seek, change, the work of migration cable, whole working process does not need the cable to have a power failure, and safe and reliable, has solved on -the -spot cable and has distinguished the problem of checking the difficulty.