This paper presents a single-domain boundary element method (BEM) for linear elastic fracture mechanics analysis in the two-dimensional anisotropic bi-materials. In this formulation, the displacement integral equation is applied on the outer boundary only, and the traction integral equation is applied on one side of the crack surface only. A special interfacial crack-tip element was introduced to capture exactly the oscillatory behavior. The computer program with the FORTRAN code has been developed to effectively calculate the stress intensity factors (SIFs) of an interfacial crack within anisotropic bi-materials. This BEM program has been verified having a good accuracy with the previous researches. Furthermore, by analyzing the different anisotropic degree of interfacial crack in an infinite domain, we found that the stress intensity factors of interfacial crack tips had apparent influence by the geometry forms of cracks and media with different anisotropic degrees.