  In this article, we analyze the vertex $D^*D^*\rho$ with the light-cone QCD
sum rules. The strong coupling constant $g_{D^*D^*\rho}$ is an important
parameter in evaluating the charmonium absorption cross sections in searching
for the quark-gluon plasmas. Our numerical value for the $g_{D^*D^*\rho}$ is
consistent with the prediction of the effective SU(4) symmetry and vector meson
dominance theory.
