Aim: The ATRIA score was developed to assess the probability of an ischemic stroke in patients with atrial fibrillation (AF). The modified ATRIA (M-ATRIA) risk score incorporates predictive risk variables for coronavirus disease 2019 (COVID-19). As a result, we looked into the association between the M-ATRIA risk score and the risk of in-hospital death in COVID-19 patients.Materials and Methods: The data of 595 inpatients in the COVID-19 research were evaluated retrospectively and separated into three groups based on the M-ATRIA scoring system. The M-ATRIA score used the troponin I level as a parameter in place of the proteinuria criterion in the ATRIA score. Those with a score between 0 and 5 were classified as group 1 (n = 269), those with a score of 6 as group 2 (n = 64), and those with a score of 7 and above were classified as group 3 (n = 162). In-hospital death, mechanical ventilation, and admission to the critical-care unit were all considered adverse clinical events.Results: The M-ATRIA risk score associated with adverse clinical events (all, p < 0.001). An M-ATRIA score of 6, an M-ATRIA score greater than 7, procalcitonin, and C- reactive protein were found to be independent predictors of in-hospital mortality in the multivariate logistic regression analysis. In the ROC analysis, an M-ATRIA score of 4.5 or above predicted in-hospital mortality with a sensitivity of 90.2% and a specificity of 58.9%. Conclusion: Regardless of the status of AF, the M-ATRIA risk score computed at admission may be a valuable tool for predicting in-hospital mortality in COVID-19 patients.