The ratio Rk = GAMMA(K+- -> e+-nu))/GAMMA(K+- -> mu+-nu) between the two leptonic decay rates of charged kaons is precisely predicted within the Standard Model. A recent theoretical work noticed that SUSY extensions of the SM can induce mu-electron universality violation in such a way to introduce a shift of the Rk value up to few % respect to SM prediction. Presently the experimental relative error of Rk, that includes also the last two recent measurements from NA48 and KLOE,is around 1.3% A new precise measurement of Rk can be of extreme interest in order to have a more stringent test of the SM. During summer 2007 the NA62 collaboration performed a dedicated period of measurements at the CERN SPS in order to achieve both the statistical and systematic accuracy for a 0.5 % relative error. A sample of about 110000 K+ -> e+nu decays has been collected and special runs dedicated to the study of the main sources of systematic effects have been performed. The experimental set-up and the analysis strategy will be described.