  \noindent We show using the entropy function formalism developed by Sen
\cite{Sen:2005wa} that the boundary term which arises from the Einstein-Hilbert
action is sufficient to yield the Bekenstein-Hawking entropy of a near horizon
extremal black hole which is asymptotically flat. However, for asymptotically
AdS black hole the bulk term due to the cosmological constant also plays an
important role apart from the surface term in the entropy function approach.
