  For the BTZ black hole in the Einstein gravity, a statistical entropy has
been calculated. It is equal to the Bekenstein-Hawking entropy. In this
article, its statistical entropy in the higer curvature gravity is calculated
and shown to be equal to one derived by using the Noether charge method. This
suggests that the equivalence between the geometrical and statistical entropies
of the black hole is retained in the general diffeomorphism invariant theories
of gravity. A relation between the cosmic censorship conjecture and the
unitarity of the conformal field theory on the boundary of AdS_3 is also
discussed.
