The aim of the investigation was to evaluate the neurotropic effect of brain-derived neurotrophic factor (BDNF) on the spontaneous bioelectrical activity of hippocampal neural networks according to the stage of their development in vitro. Materials and Methods. The studies were performed using hippocampal cells dissociated from C57BL/6 mice embryos (E18) and cultured on multielectrode arrays consisting of 64 electrodes (MED64, Alpha Med Science, Japan). BDNF was applied to the culture medium in concentrations 0.1, 1.0, and 10 ng/ml on days 7, 14 and 21 of the culture development in vitro. Spontaneous bioelectrical activity of dissociated hippocampal cultures was recorded within 10 min before the BDNF application. After the neurotrophin addition, the activity was recorded continuously for 35 min. The 10-minute recordings was repeated at 2 and 24 h after the BDNF application. Results. The experiments revealed that BDNF modulates the spontaneous bioelectrical activity of dissociated hippocampal cultures, starting from day 14 of culture development in vitro. The effect is manifested as increased network burst duration and in the restructuring of the pattern of spontaneous network activity without any changes in the number of spikes in a burst. BDNF neurotropic action was observed between 10 and 15 min after application with a validity period not less than 2 h. Conclusion. BDNF (0.1; 1.0; 10 ng/ml) application has a transient neurotropic effect on the spontaneous bioelectrical activity of mature neural networks starting from day 14 of dissociated hippocampal cultures development in vitro. Investigation the mechanisms of BDNF participation in synaptic transmission clarifies the role this neurotrophin in such functions of the central nervous system, as learning and memory processes. © 2015, Nizhny Novgorod State Medical Academy. All rights reserved.