During the COVID 19 pandemic, several treatments have been proposed to try to reduce the risk of hospital mortality in COVID-19 patients. In this retrospective, multicenter, open, non-randomized cohort study, the oral administration or not of calcifediol and its effects on hospital mortality were compared. 537 patients diagnosed with COVID19 were evaluated, of which 79 patients received oral calcifediol (2 capsules on entry and one on days 3, 7, 14, 21 and 28). These patients had a higher risk of presenting comorbilities compared to those who did not receive calcifediol, in addition to a lower CURB65 score for pneumonia severity (<3). However, the hospital mortality rate in the first 30 days decreased with the administration of calcifediol (from 17.5% to 5%). These findings may be limited by the sample size and the observational study.