  In this paper we find an equivalent mean-field description for asymptotically
$AdS$ black hole in high temperature limit and in arbitrary dimensions. We
obtain a class of mean-field potential for which the description is valid. We
explicitly show that there is an one to one correspondence between the
thermodynamics of a gas of interacting particles moving under a mean-field
potential and an $AdS$ black hole, namely the equation of state, temperature,
pressure, entropy and enthalpy of both the systems match. In $3+1$ dimensions,
in particular, the mean-field description can be thought of as an ensemble of
tiny interacting {\it asymptotically flat} black holes moving in volume $V$ and
at temperature $T$. This motivates us to identify these asymptotically flat
black holes as microstructure of asymptotically $AdS$ black holes in $3+1$
dimensions.
