  In this paper we found an Exact solution for massless scalar field with
cosmological constant. This exact solution generalized the Levi-Civita vacuum
solution\cite{8} to a massless scalar field,with a cosmological constant term.
This solution in the absence of the Cosmological constant recovers the
spacetime of a massless scalar field with cylindrical symmetry (\emph{Buchdahl
metric}\cite{2}). Also if the scalar field disappears, the spacetime is a
representation of de-Sitter space. We prove that the form of the metric's
function which was purposed in \cite{1} is valid even if we assume a general
form. Too we show that in which conditions this solution satisfies energy
conditions. Finally the validity of focusing theorem is proved.
