The W+W- and ZZ production cross sections are measured in proton-proton collisions at root s = 8 TeV with the CMS experiment at the LHC in data samples corresponding to an integrated luminosity of up to 5.3 fb(-1). The measurements are performed in the leptonic decay modes W+W- -> l'vl '' v and ZZ -> 2l2l', where l = e, mu and l'(l '') = e, mu, tau. The measured cross sections sigma (pp -> W+W-) =, 69.9 +/- 2.8 (stat.) +/- 5.6 (syst.) 3.1 +/- (lum.) pb and sigma (pp -> ZZ) = 8.4 +/- 1.0 (stat) +/- 0.7 (syst) +/- 0.4 (lum.) pb, for both Z bosons produced in the mass region 60 < m(Z) < 120 GeV, are consistent with standard model predictions. These are the first measurements of the diboson production cross sections at root s = 8 TeV. (C) 2013 CERN. Published by Elsevier B.V. All rights reserved.