to study an association between T455C apolipoprotein C-III (apo C-III) gene polymorphism, insulin resistance (IR), metabolic syndrome (MS) and its components in a Kyrgyz ethnic group.259 persons: 162 patients with MS and 97 sex and age matched controls without MS, diabetes mellitus and cardiovascular diseases were included in the study. Clinical examination with arterial blood pressure, anthropometric data measurement and laboratory tests for blood glucose and lipid parameters were performed in all included persons. In 140 patients test for immunoreactive serum insulin was done. DNA was extracted from blood cells and T455C polymorphism of apo C-III gene was determined by PCR method.In examined persons the most frequent was TC genotype as in group with MS as in controls. The difference on genotype's frequency between group was close to significant level (χ2 =5.48; p = 0.06) and odd ratio (OR) for MS between CC and TT carriers was 2.57 (95% CI 1.15-5.72); p = 0.019). Frequency of 455C allele in control group was--0.44 and in group with MS--0.54 (χ2 = 4.55; p = 0.036). In carriers of CC genotype there was noted that the frequency of IR (61.8% vs 23.1% vs 36.3%; p < 0.005), insulin level (11.9 [7.04-16.3] vs 5.73 [3.34-10.3] vs 7.54 [4.59-12.2] µIU/ml; p < 0.01) and HOMA index (3.14 [1.66-4.79] vs 1.46 [0.8-2.6] vs 2.05 [1.12-3.6]; p < 0.01) were significantly higher compared with TT and TC genotypes groups respectively. OR for IR between CC and TT carriers was 5.39 (95% CI 1.7-16.9; p = 0.0028). There also was an association between CC genotype and other MS components such as abdominal obesity (χ2--6.24; p--0.044, OR (95% CI--2.21 [1.03-4.82]) and high level of blood triglycerides (χ2--7.57; p--0.022, OR (95% CI) 2.5 [1.14-5.5]).In examined Kyrgyz ethnic population the most frequent was heterozygous TC genotype of T455C polymorphism of apo C-III. An association of 455C allele and CC genotype with MS, IR, abdominal obesity and high level of triglycerides was revealed. Key words: apolipoprotein C-III; T455C gene polymorphism; metabolic syndrome, insulin resistance.