Abstract: A newly developed two-phase,multi-region continuum model is used to numerically simulate the coupled momentum,heat and mass transport phenomena occurring in Falling Film Crystallization of binary organic melt of naphthalene and thionaphthene.Basically the predicted total crystallization quantity and the naphthalene contents in the crystal are in good agreement with the experimental ones.The numerical results reveal that during Falling Film Crystallization process a crystal layer is formed and grows up,accompanyed by a wide mushy region growing between outside melt and the crystal layer.The present continuum model can be easily and well used in treating the solid-liquid phase change problems with irregular inner free interface.