  We investigate the entanglement spectrum of the ground state of
Su-Schrieffer-Heeger-Hubbard model. The topological phases of the model can be
identified by degeneracy of the largest eigenvalues of entanglement spectrum.
The study of the periodic boundary condition is enough to obtain the phase
diagram of the model, without the consideration of the open boundary condition
case. Physical interpretation about the bulk-edge correspondence in the
entanglement spectrum is presented. The method of the entanglement spectrum can
be applicable in studying other topological phases of matter.
