Introduction: Endothelial function (EF) can be performed at the bedside, becoming relevant and reliable instrument in clinical practice in hospitalized patients by COVID-19. Objectives: To compare EF indices during hospitalization for COVID-19 and to evaluate gender differences in survival. Methods: All patients diagnosed with COVID-19 were invited to participate as soon as they arrived at hospital. EF was assessed by vasodilation endothelium-dependent brachial vascular function using ultrasonography (Sonosite turbo M) by an experienced evaluator. The patients data were extracted from medical records and were followed until death or discharge. Results: We evaluated 175 patients with COVID-19, in which 107 (61%) were men and 68 (39%) were women. Men (18%) died more than women (6%) in an average period of 11 hospital days (p=0.01) and needed more intensive care unit (ICU) (p<0.01). Likewise, they had lower values of shear stress FMD (Men: 50±33; Women: 70±39; p<0.01) and relative flow-mediated dilation (FMD%) (Men: 0.35±5.5; Women: 2.09±6.2; p=0.05). In Kaplan Meyer?s analysis, men had a higher probability of death during hospitalization by COVID-19 than women (Log-rank test, p=0.04). Conclusions: Men hospitalized for COVID-19 are more likely to die and have endothelial dysfunction when compared to women. In this way, our findings may direct researchers towards studies focused on therapies that consider differences between genders for the improvement of endothelial dysfunction in patients hospitalized for COVID-19.