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Solidification shrinkage has been recognized as an important factor for macrosegregation formation.An arbitrary Lagrangian-Eulerian (ALE) model is constructed to predict the macrosegregation caused by thermal-solutal convection and solidification shrinkage.A novel mesh update algorithm is developed to account for the domain change induced by solidification shrinkage.The velocity-pressure coupling between the non-homogenous mass conservation equation and momentum equation is addressed by a modified pressure correction method.The governing equations are solved by the streamline-upwind/Petrov-Galerkin-stabilized finite element algorithm.The application of the model to the Pb-19.2 wt％Sn alloy solidification problem is considered.The inverse segregation is successfully predicted,and reasonable agreement with the literature results is obtained.Thus,the ALE model is established to be a highly effective tool for predicting the macrosegregation caused by solidification shrinkage and thermal-solutal convection.Finally,the effect of solidification shrinkage is analyzed.The results demonstrate that solidification shrinkage delays the advance of the solidification front and intensifies the segregation.