Objective. Neurotoxic metabolites of the kynurenine pathway are thought to be implicated in the pathogenesis of schizophrenia. The enzyme indoleamine 2,3-dioxygenase (IDO) catalyzes the initial step of the kynurenine pathway that converts tryptophan to kynurenine metabolites. IDO is induced by proinflammatory cytokines. We studied IL-1 T-511C (rs16944), IL-1 C3954T (rs1143634), IDO VNTR and IDO rs9657182 polymorphisms in patients with schizophrenia and controls. Material and methods. Genotyping was performed in 296 patients with schizophrenia (ICD-10 F20.0) and 355 healthy controls. Results. The multiple dimension reduction (MDR) analysis revealed a combination included alleles С (T-511C), Т (C3954T), V1 (VNTR) and С (rs9657182), which was associated with schizophrenia (OR 3,3 CI 95% 2,3-4,8). Conclusion. This is the first report of the interaction between IL-1 and IDO genes. Further research into genes of the kynurenine pathway is needed.