  A search for the charged lepton flavor violating decay $J/\psi\to
e^{\pm}\tau^{\mp}$ with $\tau^{\mp} \to \pi^{\mp}\pi^0\nu_{\tau}$ is performed
with about $10$ billion $J/ \psi$ events collected with the BESIII detector at
the BEPCII. No significant signal is observed, and an upper limit is set on the
branching fraction $\mathcal{B}(J/\psi\to e^{\pm}\tau^{\mp})<7.5\times10^{-8}$
at the 90$\%$ confidence level. This improves the previously published limit by
two orders of magnitude.
