  The width of the decay $\tau^{-} \to \pi^{-} \pi^{0} \nu_\tau$ was calculated
in the extended NJL model. Contact interaction of $W$ boson with pion pair as
well as the contribution of the $\rho$ mesons in ground and first radial-exited
states are taken into account. The sum of the contact diagram and diagram with
intermediate $\rho$ meson in the ground state leads to the result which
coincides with the result of the vector-dominance model. Our results are in
satisfactory agreement with experimental data.
