Four most widely used models of hadronic interactions at high energies implemented in CORSIKA program were compared basing on the simulation of the first nucleus–nucleus interactions of cosmic rays with the atmosphere. For this comparison the distributions of the number of produced particles of different types were obtained, as long as the mean values of these numbers. The dependences of the fraction of the collision energy carried by different secondary particles on the mass of the primary particle were calculated for each model. The check of the electric charge conservation law implementation was performed. Comparison shows vast differences between the models in some cases that may result in different interpretation of experimental data.