<b>Background and Objective:</b> Viremia due to SARS-CoV-2 lead variety of biochemical change in the human body, which play a crucial role in the activation of the coagulation cascade causing thrombotic complications and coagulopathies. The study aimed<i> </i>to ascertain the D-dimer level as a biological mediator in COVID-19 patients in Khartoum state and compare the results to the control group. <b>Materials and Methods:</b> A cross-sectional study was conducted during the period of August to December, 2021, including 50 healthy patients and 50 COVID-19 patients, blood samples were collected from study groups for measurement of D-dimer level using an I Chroma device. Statistical analysis was conducted using SSPS version 21. <b>Results:</b> This study revealed a statistically increased D-dimer level among COVID-19 patients compared with the control group (2000-10000 vs. up to 500 ng mL<sup></sup><sup>1</sup>), respectively. <b>Conclusion:</b> Viremia induced by COVID-19 infection can cause a high D-dimer level which can lead to thrombosis event or bleeding tendency.
Keywords: D-dimer; SARS-CoV-2; coagulation cascade; hyper coagulopathy; thromboembolism; thrombosis; viremia.