COVID-19 is an infectious disease caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV2). Depending on the severity of the disease, fever, cough, shortness of breath, more severe pneumonia and death may occur. The aim of this study is to compare some blood parameters between adult male and female patients with COVID-19 to understand the effect of gender on disease pathogenesis. For this purpose, the levels of blood serum the D-dimer, white blood cells, monocyte, lymphocyte, platelet, glucose, hemoglobin and Prothrombin Time/INR were measured in a total of 3101 COVID-19 patients whose 1649 were males and 1452 were females. Statistically significant differences were observed in platelet, white blood cells, Prothrombin Time/INR, hemoglobin and monocyte levels while no differences were detected in lymphocyte, D-dimer, and blood glucose levels between male and female patients. The results indicate that platelet, white blood cells, Prothrombin Time/INR, hemoglobin and monocyte levels were significantly higher in males as compared to female patients with COVID-19.