In this paper, a simple but highly accurate analytical method to evaluate stress intensity factors based on an element overlay technique is presented. When a crack exists in a structure, we need to analyze its global deformation as well as local deformation field around the tip of the crack. This naturally leads us to a consideration on some kind of multi-scale analysis strategies. Thus, we adopt the element overlay technique (S-FEM) which is a kind of multi-scale methodologies. In this paper, we present i) numerical implementation of element overlay technique (S-FEM), ii) method to calculate stress intensity factors (virtual crack closure-integral method, VCCM), iii)accuracies of evaluated stress intensity factors and iv) some discussions.