COVID-19, provoked by SARS-CoV-2, constitutes a global health issue with high rates of mortality. The presence of diabetes mellitus is associated with severe coronavirus COVID-19 as it is related to increased death rates in patients admitted to the intensive care unit. Acute kidney injury is a frequent complication among patients hospitalized for COVID-19 and is met with high morbidity and mortality. Here, we present a case of a diabetic patient with acute kidney injury, metformin-associated lactic acidosis, and COVID-19. Lactic acidosis is a relatively rare but noteworthy complication of metformin use. However, the combination of those life-threatening situations could prove fatal for the patients despite optimal medical care.