  By measuring Drell-Yan massive lepton-pair's angular distributions, we can
identify the polarization of the virtual photon of invariant mass $Q$ which
decays immediately into the lepton-pair. In terms of a modified QCD
factorization formula for Drell-Yan process, which is valid even if $Q_T\gg Q$,
we calculate the massive lepton-pair's angular distributions at large $Q_T$. We
find that the virtual photons produced at high $Q_T$ are more likely to be
transversely polarized. We discuss the implications of this finding to the
J/$\psi$ mesons' polarization measured recently at Fermilab.
