SARS-Cov2 coinfection with other respiratory viruses is very rare. Adenovirus coinfection is even more unusual. We report the case of a patient with poorly controlled diabetes, and he was admitted to the emergency department because of severe COVID-19 infection. He had unfavorable prognostic factors such as moderate oxygen impairment, positive D-dimer, increased lactate dehydrogenase and ferritin. Adenovirus was isolated in a respiratory viral panel. He developed acute respiratory distress syndrome and required pronation and neuromuscular relaxation in the intensive care unit. Hydroxychloroquine was administered as suggested by the national guidelines. The symptoms resolved, and hospital discharge was indicated. COVID-19 association with another respiratory virus is related with adverse clinical outcomes, such as shock, ventilatory support requirement and greater lymphopenia and thrombocytopenia.