Neurotrophic factors (NTFs) have the unique potential to support neuronal structure, neuronal function, and stimulation of nerve growth in physiological environment and in case of injured nervous system. Numerous studies conducted over the last 20 years have provided evidence for the therapeutic potential of NTFs. However therapeutic use of NTFs still is hampered by many obstacles. Major problems are inability to cross the blood-brain-barrier and adverse effects resulting from the broad exposure of the nervous system and other structures to NTFs action. Viral vectors hopefully allow the targeted delivery of NTFs while providing a long-lasting supply in therapeutic doses. In this review, we consider some of experiments in animal model with use of NTFs. These insights had let to the first clinical trials with NTFs. Clinical trials to be continued over the next years will allow to determine whether NTFs are efficient in prevention and therapy of neurodegenerative diseases such as Alzheimer disease, Parkinson’s disease, Huntington disease or multiple sclerosis.