  We calculate in perturbative QCD the transverse momentum broadening of vector
bosons in heavy ion collisions at the Large Hadron Collider (LHC). We predict
transverse momentum broadening of $W/Z$ bosons constructed from their leptonic
decay channels, which should be a clean probe of initial-state medium effect.
We also predict the upper limit of transverse momentum broadening of J/$\psi$
and $\Upsilon$ production as a function of N$_{\rm part}$ at the LHC energy.
