The brain extracellular matrix is secreted by neurons and glial cells and represents a molecular net comprised of polysaccharides and proteins, fulfilling the space between cells in the tissue. A complex structure and ubiquitous localization of extracellular matrix underlie its involvement in numerous important brain functions, such as diffusion regulation, molecular cell-to-cell interactions, synaptic plasticity and learning. Additionally, the brain extracellular matrix participates in regeneration of neuronal connections after brain and spinal cord injuries. The ability to regenerate connections attenuates by the fast proliferation of the brain extracellular matrix, when its degradation leads to regeneration improvement. Therefore, the brain extracellular matrix represents an important direction of clinical research and possible target for therapeutic interventions. Here we not only describe the structure of the brain extracellular matrix and its sites of localization in the brain, but also make an overview of the influence of the brain extracellular matrix in synaptic plasticity, learning and memory. This review describes the role of the brain extracellular matrix for connection recovery after brain and spinal cord injuries. Here, we highlight the positive ability of enzymatic removal of extracellular matrix component — chondroitin sulphate proteoglycans by chondroitinase ABC to promote restoration of neuronal connections. In conclusion, we discuss possible side effects of treatments requiring the enzymatic removal of chondroitin sulphate proteoglycans on synaptic plasticity and speculate about future development of the field of the brain extracellular matrix research.