  The capabilities of the CMS experiment to study the low-x parton structure
and QCD evolution in the proton and the nucleus at LHC energies are presented
through four different measurements, to be carried out in Pb-Pb at sqrt(s_NN) =
5.5 TeV: (i) the charged hadron rapidity density $dN_{ch}/d\eta$ and (ii) the
ultraperipheral (photo)production of Upsilon; and in p-p at sqrt(s) = 14 TeV:
(iii) inclusive forward jets and (iv) Mueller-Navelet dijets (separated by
$Delta\eta\gtrsim$ 8).
