The Marburg I polymorphism (G511E) in gene was listed as one of the risk factor for idiopathic DVT among the western population. The frequency of Marburg I polymorphism in India is presently not known. Fifty DVT cases and 50 healthy controls were tested for Marburg I polymorphism using ARMS-PCR technique. The thrombophilic risk factors (Protein C, Protein S, Antithrombin III, Factor V Leiden and antiphospholipid antibodies) were also determined. Marburg I polymorphism (heterozygous) was found in 2 patients (4%) but not in control subjects. These two cases did not have any other thrombophilia markers. Among the thrombophilic markers, heterozygous FVL mutation, PS, PC, AT deficiencies and antiphospholipid antibodies were seen in 10%, 10%, 6%, 6% and 8% of the patients respectively. The controls showed only the presence of antiphospholipid antibodies in 6% of subjects. Marburg I polymorphism among Indians DVT patients was determined for the first time. Its incidence was found in 4% of cases and not in controls. Although not statically significant this may be considered as one of the contributory risk factors for the development of DVT. A larger study is required for the validation of data.© Indian Society of Hematology and Blood Transfusion 2019.