For the tendency analysis of copper converter inner-lining wear,a new method of infrared sequential images registration based on the isotherm contour features was proposed. The most similar isotherm contour was sought by centroid distance function and Fourier descriptor. The parallelism point set was given on the similar isotherm contour,and the images registration space was built by projective transformation. The image registration problem was converted into the least square estimation problem of standard parameter matrix. The test result shows that the isotherm contour matching and images registration are found rapidly and simply by the method,which may attain the analytical precision of smelting plant.