In this paper, the changes of energetic intensity of Cern neutrinos during an experiment are analysed. For the analysis of energetic intensity of neutrinos, the theory of covariance functions was applied. The estimates of cross-covariance functions of digital data of energetic intensity of neutrinos or autocovariance functions of single data are calculated according to the random functions formed in the energetic intensity measuring data arrays in theform of vectors. The covariance functions have been calculated by varying the quantisation interval on the energetic scale and applying the computer program developed using MATLAB 7 package of procedures.