  The close binary V337 Aql consists of two early B-type components with an
orbital period of 2.7339 d. New multi-band photometric observations of the
system together with published radial velocities enabled us to derive the
absolute parameters of the components. The simultaneous light and radial
velocity curves solution yields masses and radii of
\emph{M$_{1}$}=17.44$\pm$0.31 \emph{M$_\odot$} and \emph{R$_{1}$}=9.86$\pm$0.06
\emph{R$_\odot$} for the primary and \emph{M$_{2}$}=7.83$\pm$0.18
\emph{M$_\odot$} and \emph{R$_{2}$}=7.48$\pm$0.04 \emph{R$_\odot$} for the
secondary component. Derived fundamental parameters allow us to calculate the
photometric distance as 1355$\pm$160 pc. The present analysis indicates that
the system is a near-contact semi-detached binary, in which a primary star is
inside its Roche lobe with a filling ratio of 92 percent and the secondary star
fills its Roche lobe. From \emph{O-C} data analysis, an orbital period decrease
was determined with a rate of -7.6 $\times$ 10$^{-8}$ yr$^{-1}$. Kinematic
analysis reveals that V337 Aql has a circular orbit in the Galaxy and belongs
to a young thin-disc population.
