An algorithm for converting the three-dimensional(3D) electromagnetic(EM) data calculated on finite element(FEM) nodes into a finite difference(FDM) format was proposed in order to perform efficient FEM/FDM-coupled computations for solidification transport phenomena(STP) under various EM fields.The present method is available for arbitrary spatial relationships between the irregular FEM and FDM mesh patterns based on the interpolation principle of FEM.The corresponding programs for the data conversion and post-processing for 3D-displays were developed using Fortran-95 language and the QuickWin module on a Visual-Fortran-6.6A platform.The sample calculations and displays for the system of a cold-crucible EM directional solidification show that the proposed FEM-FDM data conversion algorithm is successful and effective.The present work will provide reliable EM field data and an efficacious 3D graphic analysis tool for the subsequent EM-STP-coupled computations with an FDM-based numerical method.