Background: Role of laboratory parameters in prediction of COVID-19 severity and the need for ICU admission is not well established and needs further investigations. Objective: This study aimed to evaluate the role of different laboratory parameters, as a minimally invasive method, in prediction of COVID-19 severity and the need for ICU admission. Patients and methods: Two hundredCOVID-19 confirmed patients were admitted to Zagazig University Isolation Hospitals. They were divided into 2 groups according to disease severity. Group I included 100 patients admitted to ICU with severe COVID-19 infection and group II that included 100 patients with mild to moderate COVID-19 infection. Results: There was a statistical significance increase in WBCs, PNL and neutrophil/lymphocyte ratio and decrease in lymphocyte among sever cases compared to mild cases. WBCs, lymphocyte, PNL, neutrophil/lymphocyte ratio, urea, d-dimer, LDH, ferritin and CRP had significant validity in prediction of severe cases with accuracy of 63%, 65%, 66%, 70%, 68%, 66%, 65%, 66.5% and 64.5% respectively. WBCs, lymphocyte, PNL, neutrophil/lymphocyte ratio, urea, d-dimer, LDH, ferritin and CRP had significant validity in prediction of mortality among the studied cases with accuracy of 55.5%, 55.5%, 63%, 64.5%, 63.5%, 57.5%, 56.5%, 65% and 62% respectively. Conclusion: The studied biomarkers can be used as an important assistant in clinical practice at ICU admission to improve prognosis, guide treatment and minimize the mortality rates.