Lepton Flavour Universality implies the equality of the coupling between the gauge bosons and the three families of leptons. Semileptonic and rare decays of b quarks provide an ideal laboratory to test this property and to search for physics beyond the Standard Model. In these proceedings a review of the recent Lepton Flavour Universality tests performed using data collected by the LHCb experiment in 2011 and 2012 are presented.