This study aimed to determine COVID-19 bacterial co-infection incidence and assess the severity and outcome among patients in Zagazig University quarantine ICUs. Methods: This prospective cohort study was carried out on moderate and severe COVID-19 patients admitted to Zagazig University quarantine intensive care units. Full history was taken with complete physical examination, vital signs, laboratory investigations, bacterial co-infection assessment (within 48 hrs of admission) in form of persisting fever or leucocytosis (neutrophilia) and high procalcitonin with blood or sputum cultures and follow up the patients till discharge or death. Results: Among 180 studied COVID-19 patients there was 21.1% of them had bacterial co-infection while 78.9 % were without bacterial co-infection. There were 8.9% positive blood cultures and 16.1% positive sputum cultures. There were significantly higher percentages of severity, CPAP need, and death rate among patients with bacterial co-infection. There was a statistically significant difference regarding the duration of ICU stay with a higher median in COVID-19 without bacterial co-infection. Conclusions: The incidence of COVID-19 bacterial co-infection among patients in Zagazig University quarantine ICUs was 21.1% with Klebsiella organism the most causative organism and there were significantly higher percentages of severity and death rate among COVID-19 patients with bacterial co-infection.