  We make a detailed analysis of the $BB\rho(DD\rho)$ and
$B^*B\rho(D^{*}D\rho)$ strong couplings $g_{BB\rho}(g_{DD\rho})$ and
$g_{B^*B\rho}(g_{D^{*}D\rho})$ using QCD light cone sum rules(LCSR). The
existing some negligence is pointed out in the previous LCSR calculation on
$g_{B^*B\rho} (g_{D^{\ast}D\rho}$) and an updated estimate is presented. Our
findings can be used to understand the behavior of the $B,D \to \rho$
semileptonic form factors at large momentum transitions.
