Cerebrolysin is the drug which contains peptides derived from the brain of a pig. It is used in neurological practice for recovery of stroke patients and treatment of dementia. Despite the evidence-basis and some experimental studies, the distinct mechanisms of pharmacological action of this drug remain unclear for most neurologists. In this paper, we present results of a molecular-biological analysis of peptide content of cerebrolysin. We have demonstrated the presence of active peptide fragments of nerve growth factor, enkephalins, orexin, halanin. The results of current clinical and experimental studies of cerebrolysin have been compared. The activity of above-mentioned neuropeptides explain experimental and clinical details of all known effects (neurotrophic, neuroprotective and immunomodulating) of cerebrolysin in ischemic and neurodegenerative CNS injuries. The analysis allowed to make conclusions about mechanisms of cerebrolysin action that were important for increasing the efficacy of this drug in clinical practice.