In a number of schizophrenia concepts, the neurocognitive deficiency is distinguished to a separate domain along with positive and negative disorders, and it is an important predictor of the unfavourable prognosis of the course of the disease and the development of persistent social dysfunction. The contribution of genetic mechanisms has been proven in the variability of attention instability and long-term memory impairment. Brain derived neurotrophic factor (BDNF) regulates a number of aspects of cell differentiation and survival; it is also required in synaptic plasticity and long-term potentiation (that determine learning and memory). In this study, we compared cognitive functions in schizophrenia cases and healthy controls. We also evaluated associations between cognitive functions and a BDNF gene polymorphism. It was a complex evaluation of 550 schizophrenia patients and 485 healthy persons. The BDNF polymorphism rs6265 was not associated with schizophrenia. Cognitive functions were evaluated in 160 schizophrenia cases and 106 healthy controls using the BACS scale. The indicators of cognitive function in schizophrenia cases were significantly worse in comparison with healthy subjects. Associations of genotypes of polymorphism rs6265 of the BDNF gene were detected with performing subtests of the BACS scale.