BACKGROUND Organochlorine pesticides (OCPs) are endocrinal disruptors that tend to accumulate in adipose tissue and have been found to be associated with Metabolic Syndrome (MS). OBJECTIVE 1. To measure serum OCP levels in patients of MS and control subjects, 2. To identify differences, if any, in serum OCP levels, in patients with MS and control subjects. METHODS Cross-sectional study was conducted in the Departments of Medicine and Biochemistry at University College of Medical Sciences (UCMS) and Guru Teg Bahadur Hospital (GTBH), Delhi. Nine OCPs [α-HCH (Hexachlorocyclohexane), β-HCH, g-HCH, α-endosulfan, β-endosulfan, aldrin, dieldrin, p, p'-DDT (Dichloro-diphenyl-trichloro-ethane), and p, p'-DDE (Dichloro-diphenyl-dichloro-ethylene)] were studied. Fifty subjects ≥18 years with MS (study group) and 50 age and sex-matched controls were included in the study. METHODS (1) Persons having chronic occupational exposure to OCPs such as workers of pesticide factories, (2) Recent exposure to OCPs within 4 weeks. RESULTS Levels of all nine OCPs were higher in cases as compared to controls. However, only the mean value of β-HCH in cases (8.40 ± 8.64 ng/ml) was significantly (P < 0.001) higher as compared to controls (2.58 ± 2.34 ng/ml). After adjustment of confounding factors like age, sex, smoking, alcohol, and body mass index (BMI), only β-HCH and aldrin levels were positively and significantly associated with the risk of having MS. Adjusted Odds Ratio (OR) was 1.34 [CI = 1.14-1.57 (P < 0.001)] and 1.23 [CI = 1.01-1.50 (P = 0.045)], respectively. CONCLUSIONS There was a significant association of β- HCH and aldrin levels with MS.