The invention discloses a method for identifying a defect profile of a pseudo three-dimensional magnetic flux leakage signal based on a normal component. The method comprises the following steps: selecting an identification area from a piece to be tested; filtering detected data to obtain a normal component of a magnetic flux leakage signal; multiplying a horizontal differential signal by a firstpreset multiple to obtain a horizontal component of a pseudo magnetic leakage signal; multiplying a vertical differential signal by a second preset multiple to obtain a vertical component of the pseudo magnetic leakage signal; performing pseudo three-dimensional magnetic flux leakage signal synthesis operation on the normal component of the magnetic flux leakage signal, and the horizontal component and the vertical component of the pseudo magnetic flux leakage signal to obtain a synthesized magnetic flux leakage signal; and selecting a preset threshold value to obtain a defect identification profile. According to the method, an approximate value of the horizontal component and the vertical component of the magnetic flux leakage signal can be derived from the normal component of the magnetic flux leakage signal to further construct a pseudo three-dimensional magnetic flux leakage signal so as to realize defect profile identification; and the method has higher solving precision and better identification effect compared with the traditional one-dimensional magnetic flux leakage signal defect profile recognition.