Evidence supports a sex disparity in clinical outcomes of COVID-19 patients, with men exhibiting higher mortality rates compared to women. We aimed to test the correlation between serum levels of sex hormones total testosterone, estradiol (E2), estradiol to testosterone (E2/T) ratio, progesterone), prolactin and 25-hydroxyvitamin D 25(OH)D and markers of inflammation, coagulation and sepsis at admission in hospitalized men with COVID-19. We conducted an exploratory retrospective study including symptomatic men with confirmed SARS-CoV-2 infection who were consecutively admitted to our Institution between April 1 and May 31, 2020. Patients were divided into survivors (n=20) and non-survivors (n=39). As compared to survivors, non-survivors showed significantly higher median neutrophil-to-lymphocyte ratio (NLR) values, D-dimer and procalcitonin (PCT) levels, along with significantly lower median 25(OH)D levels and total testosterone levels. Non-survivors exhibited significantly higher median values of E2/T ratio (a marker of aromatase activity). Spearman's correlation analysis revealed that total testosterone levels were significantly and inversely correlated with NLR, high-sensitivity C-reactive protein (hsCRP), interleukin-6, D-dimer and PCT. Conversely, E2/T ratio values were significantly and positively correlated with the aforementioned markers and with white blood cell (WBC) count. In a multivariate analysis performed by a logistic regression model after adjusting for major confounders (age, body mass index, hypertension and cardiovascular disease, diabetes mellitus and malignancy), total testosterone levels were significantly and inversely associated with risk of COVID-19-related in-hospital mortality. Low total testosterone levels and elevated E2/T ratio values at admission are associated with hyperinflammatory state in hospitalized men with COVID-19. Low total testosterone levels at admission represent an independent risk factor for in-hospital mortality in such patients. Therefore, total testosterone and E2/T ratio may serve as prognostic markers of disease severity in this population.