  The correlation between the elliptic flow $v_2$ scaled by the impact
parameter $b$ and the shear viscosity $\eta$ as well as the specific viscosity
$\eta/s$, defined as the ratio of the shear viscosity to the entropy density
$s$, is investigated for the first time in intermediate-energy heavy-ion
collisions based on an isospin-dependent quantum molecular dynamic model. The
elliptic flow is calculated at balance energies to exclude the geometric
influence such as the blocking effect from the spectators. Our study shows that
$v_{2}/b$ decreases almost linearly with increasing $\eta$, consistent with
that observed in ultra-relativistic heavy-ion collisions. On the other hand,
$v_{2}/b$ is found to increase with increasing $\eta/s$.
