Introduction: Pro-thrombotic changes are stimulated by Corona Virus as it has an affinity forendothelium and lung structures and this may explain its association with thrombotic events,reduction of pulmonary gas exchange, respiratory distress, and death. D-dimer is a specific markerof the breakdown of a fibrin clot and has been used as a diagnostic and prognostic marker in VTEand other coagulation disorders. Objectives: The objective of this study was to assess thecorrelation of the D-Dimer levels and disease severity among COVID-19 patients. Materials andmethods: This is a retrospective study done over 6 months from July 2020 to December 2020 in atertiary care hospital in Bangalore. All the COVID- 19 positive cases who were admitted to ourhospital were audited regarding the D-dimer levels during admission and the course of thetreatment. Results: Coagulation disorder occurred at the early stage of COVID-19 infection, with1066 (57.7%) patients having increased D-dimer levels. Out of 1846 COVID 19 patients 106(5.7%)patients died due to complications. 106 patients who deceased, all the patients had anincreased D dimer value either in the first lab test or in the consecutive tests. Among 106 patients56(52.8%) patients had increased D-dimer at the first lab test, 32 (30.1%) had D-dimer increasedat the second and 18(16.98%) in third lab tests. The increased D-dimer levels were closelyassociated with the progression of the disease and also the changes in the CT imaging. Conclusion:The increase in D-Dimer levels also increased the complications in the COVID-19 patient. So it isnecessary to continuously monitor D-dimer levels and labelled anticoagulation as management toolsfor COVID-19 disease to prevent complications and reduce interventions.