The measurement of W and Z plus jets final states at the LHC allows for stringent tests of perturbative QCD calculations in the context of the Standard Model and is sensitive to the possible presence of new physics. A study of jet production in association with a vector boson in proton-proton collisions at a 7 TeV center-of-mass energy is presented, using data collected with the CMS detector. The measured jet multiplicity distributions, corrected for efficiency and unfolded for detector effects, are compared with theoretical predictions. The study includes the measurement of the normalized inclusive rates of jets and of the ratio W/Z. A test of the jet multiplicity scaling at sqrt(s) = 7 TeV is also presented.
