In terms of the characteristic of temperature field, a precise finite element model (FEM) was established for the sandwich composite structure. The FEM was a 3D hexahedral model. A variety of properties between structure layers was considered in the established FEM. The interpolation function that the value of the function was continuous but the derivative of the function was not continuous at the interface node of layers was chosen to be the field function of the established finite element for the direction of thickness. The corresponding heat transfer FEM equation based on the presented element was also obtained. In terms of the characteristic of the nonlinear ordinary differential heat transfer FEM equation that the thermal property of the material is affected by temperature, the dynamical equation solution was improved. The improved methods will avoid iteration in each time step in the solution process. The numerical example will show the efficiency and reliability of the present method.