Abstract: In this paper,the J-integral for a heterogeneous strip with a crack in the trans-verse hard layer,which is a typical case of welded joints,is analyzed by elasto-plastic FEM under the plane stress condition.The results obtained show that the J-integral remains path-independent in spite of the mechanical heterogeneity.The narrower the hard layer is,the larger the J-integral value at the same load level will be.This coincides with the results of our earlier COD analysis.