  We study the critical behavior of the single-site entanglement entropy S at
the Mott metal-insulator transition in infinite-dimensional Hubbard model. For
this model, the entanglement between a single site and rest of the lattice can
be evaluated exactly, using the dynamical mean-field theory (DMFT). Both the
numerical solution using exact diagonalization and the analytical one using
two-site DMFT gives S-Sc \propto \alpha \log_{2}[(1/2-Dc)/Dc](U-Uc), with Dc
the double occupancy at Uc and \alpha < 0 being different on two sides of the
transition.
