Objective: Bacterial and fungal infections, antimicrobial resistance (AMR) results of bacterial agents, and the effect of the pandemic on AMR were evaluated in hospitalized COVID-19 patients. In addition, the detected AMR rates were compared with the AMR rates of the pre-pandemic period. Patients and Methods: The isolates grown in respiratory and blood samples of adult patients hospitalized with the diagnosis of COVID-19 between March 2020 and December 2020 were evaluated retrospectively. The same data in hospitalized patients before the pandemic, between March and December 2019, were evaluated retrospectively. Results: A total of 724 samples were included in the study. The superinfection rate was found to be 15.3%. The most frequently isolated microorganisms are; Acinetobacter baumannii (34.4%), Staphylococcus aureus (10.8%), Klebsiella pneumoniae (9.7%) and Pseudomonas aeruginosa (7.3%). The lowest resistance rates in Klebsiella pneumoniae isolates were found for aminoglycosides, in Acinetobacter baumannii isolates were found for trimethoprim-sulfamethoxazole, in Pseudomonas aeruginosa isolates were found for amikacin. When pre-pandemic and pandemic AMR rates were compared; a significant increase in amikacin resistance was detected only in Klebsiella pneumoniae isolates during the pandemic period (P:0.049). Conclusion: The data we have presented may help clinicians in the selection of antimicrobials for empirical therapy by revealing the effect of the pandemic on AMR.