We report on the first measurement of J/Psi production as a function of charged particle pseudo-rapidity density dN_ch/d_eta in pp collisions at sqrt{s} = 7 TeV with the ALICE experiment at the LHC. J/Psi mesons are detected down to p_T = 0 via their decays into e+e- pairs at mid-rapidity (|y| < 0.9) and into mu+mu- pairs at forward rapidity (2.5