BACKGROUND: During the COVID-19 pandemic, the workload of all radiologists and radiology residents, as well as other clinical physicians, has increased. INTRODUCTION: This study aims to determine the diagnostic performance of radiology residents, who effectively contribute to the diagnosis of COVID-19. METHODS: The thoracic computed tomography (CT) images of 135 patients aged 20-83 diagnosed with COVID-19 were evaluated retrospectively by five radiology residents and a radiologist with 10 years of experience. The diagnostic performance of the radiology residents in evaluating COVID-19 was assessed according to their year of residency and the patients' age and gender. Receiver operating characteristic (ROC) curve analysis was performed to determine the sensitivity and specificity of radiology residents. RESULTS: The radiology residents' performance in determining COVID-19 using CT findings was evaluated as follows: sensitivity 97.22%, specificity 88.89%, positive predictive value 90.91%, negative predictive value 96.55%, and accuracy 93.33%. According to the year of residency, the sensitivity and specificity of the radiology residents in determining COVID-19 using CT images were between 92.3% and 100%, and 71.43% and 100%, respectively. CONCLUSION: The high sensitivity and specificity of radiology residents in evaluating thoracic CT images for COVID-19 diagnosis indicate that radiologists are as important as clinical physicians in the diagnosis of COVID-19.