Introduction: COVID-19 and secondary infections developing during COVID-19 follow-up are one of the most important causes of morbidity and mortality in intensive care units (ICU). In this study, we aimed to determine the frequency, microbiology, risk factors, and outcomes of secondary bacterial pneumonia in hospitalized patients due to COVID-19. Methodology: We studied all patients with bacterial pneumonia developed in patients with severe COVID-19 infection in the COVID-19 intensive care unit in a single-center hospital between March 16, 2020 and June 17, 2020. Patients hospitalized and followed up in the ICU for respiratory failure were examined in terms of secondary infection affecting morbidity and mortality. Results: Ninety-six (20%) of 471 patients had secondary bacterial pneumonia, respectively; of the leading pathogens were Acinetobacter baumannii (44.8%) and Klebsiella pneumoniae (39.6%), followed by Pseudomonas aeruginosa (4.2%), Escherichia coli (3.1%), methicillin-resistant Staphylococcus aureus (MRSA) (3.1%), Streptococcus pneumoniae (3.1%), and Methicillin-susceptible Staphylococcus aureus (MSSA) (1%). The mortality rate among infected (75% / 47.5%) was significantly higher than in uninfected patients. Associated with the development of secondary bacterial pneumonia in COVID-19 patients; corticosteroid therapy [odds ratio (OR) 6250, 95% confidence interval (CI) 1.383-28.571, p = 0.017), corticosteroid dose (OR 8.862 CI 2.299-70.258, p= 0.006), duration of mechanical ventilation (OR 1.199 CI) 1.088-1.322, p< 0.001). Conclusions: Secondary bacterial pneumonia was found to be associated with the severity and survival of the disease in patients admitted to ICU due to COVID-19. Duration of mechanical ventilation and use of corticosteroids and high-dose corticosteroids are risk factors for secondary bacterial pneumonia.