The results of the study of the significance of axotomy in the postmortem diagnosis of diffuse axonal brain damage are presented. In the corpus callosum, two main types of changes in the processes of neurons were found: damage to the processes without mechanical rupture and axotomy. The revealed polymorphism of damage to the processes of neurons indicates the heterogeneity and staging of pathological processes caused both by the trauma itself and by developing reactive post-traumatic changes. Severe damage to the processes is secondary and not earlier than 2 days after the injury lead to axotomy, the morphological manifestation of which is retraction balls with a diameter of 15.5±6.33 μm, detected by staining with hematoxylin and eosin. Research results indicate that axotomy should not be differentiated into primary and secondary.