  A new dark energy model in anisotropic Bianchi type-III space-time with
variable equation of state (EoS) parameter has been investigated in the present
paper. To get the deterministic model, we consider that the expansion $\theta$
in the model is proportional to the eigen value $\sigma^{2}_{~2}$ of the shear
tensor $\sigma^{j}_~i$. The EoS parameter $\omega$ is found to be time
dependent and its existing range for this model is in good agreement with the
recent observations of SNe Ia data (Knop et al. 2003) and SNe Ia data with CMBR
anisotropy and galaxy clustering statistics (Tegmark et al. 2004). It has been
suggested that the dark energy that explains the observed accelerating
expansion of the universe may arise due to the contribution to the vacuum
energy of the EoS in a time dependent background. Some physical aspects of dark
energy model are also discussed.
