Although antibiotics (ABs) are ineffective against COVID-19, they are often prescribed to patients with the new coronavirus infection. Many of these prescriptions are uncalled for.The aim of the work is to assess the frequency of prescribing antibiotics to hospitalized patients with confirmed COVID-19, identify the most commonly prescribed ABs, and determine the significance of various biomarkers for the diagnosis of bacterial infection.Methods. A retrospective analysis of 190 inpatient cases with confirmed COVID-19 was carried out. The records of COVID-19 patients who were admitted to the intensive care unit were excluded from the analysis. Two groups were formed: 30 patients (group 1) with COVID-19, emergency or elective surgery, and exacerbation of chronic infectious diseases, and 160 patients (group 2) with manifestations of COVID-19 only.Results. ABs were prescribed to 189 patients upon admission to the hospital. The most frequently prescribed ABs included macrolides (63.5%), respiratory fluoroquinolones (49.7%), and third or fourth-generation cephalosporins (57.1%). ABs were administered starting from the first day of admission and until the discharge. The patients in group 2 were more often prescribed respiratory fluoroquinolones and, less often, III - IV generation cephalosporins. Moreover, macrolides were used in the treatment regimens of both groups. Longer administration of respiratory fluoroquinolones to patients in group 2 than patients in group 1 (p < 0,05) was noted. Group 2 also tended to receive longer therapy with macrolides. On admission, the patients with signs of bacterial infection had more significant leukocytosis with a neutrophilic shift, a more common increase in ESR of more than 20 mm/h and an increase in the level of procalcitonin > 0,5 ng/ml.Conclusion. ABs were administered to the overwhelming majority of hospitalized patients in the absence of clear therapeutic indications. The ABs are likely to have a minimal benefit as empirical treatment of COVID-19 and are associated with unintended consequences, including adverse effects and increased antibiotic resistance. According to our data, the most informative markers of a secondary bacterial infection in patients with COVID-19 are leukocytosis with a neutrophilic shift, an increase in ESR of more than 20 mm/h, and a procalcitonin level of more than 0,5 ng/ml.