  Recent redshift-distance measurements of Type Ia supernovae (SNe Ia) at
cosmological distances suggest that two-third of the energy density of the
universe is dominated by dark energy component with an effective negative
pressure. This dark energy component is described by the equation of state
$p_{x} = w \rho_{x}$ $(w \geq -1)$. We use gravitational lensing statistics to
constrain the equation of state of this dark energy. We use $n(\Delta\theta)$,
image separation distribution function of lensed quasars, as a tool to probe
$w$. We find that for the observed range of $\Omega_m \sim 0.2 - 0.4$, $w$
should lie between $-0.8 \leq w \leq -0.4$ in order to have five lensed quasars
in a sample of 867 optical quasars. This limit is highly sensitive to lens and
Schechter parameters and evolution of galaxies.
