Patients with COVID-19 experience multiple clinical conditions that may cause electrolyte imbalances. SARS-CoV-2 binds angiotensin I converting enzyme 2 (ACE2) of renin–angiotensin system (RAS) and causes prevalent hypokalemia. Hypokalemia is a concerning electrolyte disorder closely associated with severe complications. To evaluate frequency of hypokalemia in covid-19 patients and its correlation with disease severity and outcome. The current study was a retrospective cohort study conducted on 400 confirmed covid-19 patients above 18 years old admitted to Al Zahraa University Hospital during the period between November 2020 and March 2022.In the current study, all patients were divided according to serum potassium level and it revealed that there were 161 patients with normal potassium level (40.3%), 133 patients with mild hypokalemia (33.3%),75 patients with moderate hypokalemia (18.8% ) and 31 patients with severe hypokalemia (7.8%). More ever we found that severity of disease was associated with severity of hypokalemia but there was no association between mortality and severity of hypokalemia. HTN was the commonest comorbidity (42.3%) and corticosteroid was a risk factor for hypokalemia development in our patients. Finally, hypokalemia was associated with long hospital stay and can be used as a predictor of severity of covid-19. Hypokalemia was a common electrolyte disturbance in covid-19 patients and most cases were of mild degree. Severity of hypokalemia was associated with disease severity but had no effect on mortality. Serum potassium level should be monitored in clinical practice of covid-19 cases.