Objective. Type 1 diabetes mellitus (T1DM) is an autoimmune disease and extensive researches have been performed to reveal the association of cytokine gene polymorphisms with T1DM. Interleukin-6 (IL-6) and interleukin-12 (IL-12) were shown to trigger the inflammatory cascade both in vivo and in vitro. It has been reported that IL12B and IL6 gene polymorphisms were associated with T1DM in several populations. The aim of the present study was to investigate the role of the IL6 -572G/C and IL12B -1159C/A polymorphisms in patients with T1DM. Methods. The study comprised 130 T1DM patients, mean age 33.0 ±13.8 years, and 414 unrelated healthy subjects, mean age 38.4±8.6 years, from Tatar ethnic group (Bashkortostan, Russia). DNA was phenol-chlorophorm extracted from 8 ml EDTA-blood and used as template in PCR-RFLP. Statistical analysis was performed using Fisher's exact test. Results. IL6 -572G/C genotype freque ncy distribution did not significantly differ in patients and controls. However, after adjusting to the sex, GG genotype frequency turned to be significantly higher among T1DM females comparing to the healthy females (P=0.039). Besides, allele G ratio was higher in diabetic women than in their controls (P=0.048). From the other hand, allele C was more rare in T1DM female patients (P=0.048). IL12B -1159C/A genotype frequencies in Tatar controls (AA 59.9%, CC 3.8%, AC 36.3%) did not differ from the T1DM patients. Conclusion. Our findings provide the evidence that IL6 -572G/C polymorphism is associated with T1DM in Tatar females. Allele G (OR=2.07, CI=1.00-4.28) as well as genotype GG (OR=2.31, CI=1.03-5.17) predispose to the disease but allele C is protective (OR=0.48, CI=0.23-0.99). IL12B -1159C/A polymorphism is not associated with T1DM in Tatars.