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The paper proposes an effective general formulation for simulating unsteady state heat transfer problem with moving boundaries.The method is equipped with a correction term based on the finite element method(FEM)for spatial discretization.In dealing with the unsteady behavior,forward time marching is performed using the standard finite difference method,where the nodal temperature values at the previous time step are employed to solve the current temperature field.Due to the effect of the moving boundary,the position of the node changes with time,leading to difficulty in the handling of space-time approximation of the temperature and its gradients.We first apply simple techniques that use an extra interpolation and extrapolation operation to obtain the temperature values at locations needed for the time marching.We then introduce a novel technique with a correction term to effectively handle the moving boundary effects,without the need for the extra interpolation or extrapolation.With the correction term,one can directly use the nodal temperature values at the previous step in the time marching,in the same way as in the standard formulation of FEM for heat transfer problem with fixed boundary.A mathematical study has also been conducted to examine the theoretical basis for the correction item.Finally,intensive numerical experiments are conducted and the results are presented to demonstrate accuracy,effectiveness and stability of the proposed procedure.