  The effect of scalar and vector meson mixing on the dilepton radiation from
hot and dense hadronic matter is estimated in different isospin channels. In
particular, we study the effect of $\sigma$-$\omega$ and $\rho-a_0$ mixing and
calculate the corresponding rates. Effects are found to be significant compared
to standard $\pi$-$\pi$ and $K$-${\bar K}$ annihilations. While the mixing in
the isoscalar channel mostly gives a contribution in the invariant mass range
between the two-pion threshold and the $\omega$ peak, the isovector channel
mixing induces an additional peak just below that of the $\phi$.
Experimentally, the dilepton signals from $\rho$-$a_0$ mixing seem to be more
tractable than those from $\sigma$-$\omega$ mixing.
