Abstract: The stress intensity factors of multiple cracks are calculated by using the scaled boundary finite element method (SBFEM) considering the surface tractions. SBFEM has the advantages that it gives analytical solutions of displacements and stress fields in the radial direction and thus the stress intensity factors can be evaluated according to its definition without a particular treatment of crack tip. For the multiple crack problems, the present method can calculate the SIF by introducing the sub-structuring technique. Numerical examples show that the scaled boundary finite element method is effective with high accuracy in dealing with the multiple cracks fracture problems subjected to the surface tractions. The scope of application of SBFEM has been extended. In addition, the SBFEM can be applied to handle the crack problem of anisotropy material conveniently, some results of orthotropic material crack are provided.