  The generalized Chaplygin gas (GCG) model in spatially flat universe is
investigated. The cosmological consequences led by GCG model including the
evolution of EoS parameter, deceleration parameter and dimensionless Hubble
parameter are calculated. We show that the GCG model behaves as a general
quintessence model. The GCG model can also represent the pressureless CDM model
at the early time and cosmological constant model at the late time. The
dependency of transition from decelerated expansion to accelerated expansion on
the parameters of model is investigated. The statefinder parameters $r$ and $s$
in this model are derived and the evolutionary trajectories in $s-r$ plane are
plotted. Finally, based on current observational data, we plot the evolutionary
trajectories in $s-r$ and $q-r$ planes for best fit values of the parameters of
GCG model. It has been shown that although, there are similarities between GCG
model and other forms of chaplygin gas in statefinder plane, but the distance
of this model from the $\Lambda$CDM fixed point in $s-r$ diagram is shorter
compare with standard chaplygin gas model.
