To provide an eddy current flaw-detecting device that has a compact detector with high space resolution.

This eddy current flaw-detecting device is equipped with an excitation coil 1 that generates an eddy current in a specimen 11 by an excitation current and change in a magnetic field is generated near a damaged part, a magnetic field detector 13 that has an amorphous magnetic line 2 for detecting the change in the magnetic field, and an applied current generator 8 that supplies an application current with higher frequency than that of the excitation current to the amorphous magnetic line. The application current generator preferably generates a pulsive current with higher pulse repetition frequency than the frequency of the excitation current.