The condensation method for the analysis of viscoelastic interface crack with similar shape element is put forward. By this method, similar shape elements are generated near the crack tip, forming a substructure with a large number of similar shape elements. And then the large number of freedom degrees in substructure is condensed out. Identity of stiffness matrix between the similar shape elements is used fully during the process of condensation, The tension of bi-viscoelastic and elastic-viscoelastic material rectangle plate with the single edge crack is solved to illustrate the use of this method.