Background: Hematological parameters like total leukocyte count (TLC), neutrophil, lymphocyte, and absolute eosinophil counts (AEC), and neutrophil-to-lymphocyte ratio (NLR) are known to predict the severity of novel corona virus disease 2019 (COVID-19) patients. In the present study, we aimed to study the role of Hematological parameters in predicting disease severity in Covid 19 patients.Methods: A retrospective study was done over a period of 2 months. Patients, who were ≥ 18 years of age with COVID-19 confirmed on SARS-CoV-2 reverse transcription-polymerase chain reaction (RTPCR) and whose routine hematology counts were sent within 24 h of admission, were included in the study. Results:Total 282 patients included in the study, 62.8% were male and the average age was 47.6 ±16.9 years. The most common complaints were fever (37.2%) and cough (15.2%), Comparisons made according to real-time PCR test results revealed that while no statistically significant difference was observed between test groups (negative-positive) regarding lymphocyte and platelet lymphocyte ratio values (p>0.05), a statistically significant difference (p<0.05) was found between the test groups regarding platelet, hemoglobin, leukocyte, neutrophil, NLR and SII values.Conclusions: In conclusion, the low values for NLR, SII, absolute neutrophil and lymphocyte counts, and PLTs may have diagnostic properties concerning COVID-19.