Remote field eddy current (RFEC) technique in combination with the advantages of infinitive from skin effect and ability to detect the inner crack of metal member is characterized by its equal sensitivity to a flaw irrespective to its location in the tube wall, and has a small relationship with the magnetic field from the exciting coil. This paper applies the traditional pipeline RFECT to detection for plate member. In this paper the basis of the principle of RFEC is analyzed, the cylindrical and rectangular exciting coils are designed; the detection effect of plate and the law of magnetic flux density of two sensor models are simulated. The result of simulation shows that rectangular exciting coil can induce the directional magnetic field in the plate and RFECT can be used to detect the crack in plate and perform quantitative determination of the depth and length.