Abstract: The boundary shape identification based on the surface temperature measurement is not only a key theoretical basis for quantitative development of thermographic nondestructive technique, but also an important and difficult issue in the research of inverse heat conduction problem. When identifying the boundary shape, for ordinary algorithms, the boundary shape continually changes during the iterative process, which increases the calculation complexity and restricts practical application of the algorithm. Based on previous algorithm researches, the identification problem of interfacial geometry has been transformed into that of the distribution of effective thermal conductivities. The distribution result obtained based on the modified one-dimensional correction method is then converted to the desired boundary shape. Numerical test cases have proved that the algorithm with the transform theory which greatly reduced the calculational complexity of the identification process, is an effective method in dealing with identification problem of interfacial geometry.