  The effects of boundary impurities on the entanglement entropy in an
antiferromagnetic Heisenberg opened spin-$1/2$ chain are investigated. The
method of density-matrix renormalization-group is used to obtain the bipartite
entanglement. The entropy increases when the length of the subsystem increases.
It will approach to a constant when system length is very large. With the same
impurity interaction, qutrit impurities of spin-$1$ can increase the
entanglement entropy.
