  We present a microscopical derivation of the entropy of the black hole
solutions of the Jackiw-Teitelboim theory. We show that the asymptotic symmetry
of two-dimensional (2D) Anti-de Sitter space is generated by a central
extension of the Virasoro algebra. Using a canonical realization of this
symmetry and Cardy's formula we calculate the statistical entropy of 2D black
holes, which turns out to agree, up to a factor $\sqrt 2$, with the
thermodynamical result.
