We report a case of a 10-month infant with dual severe infection of COVID-19 and dengue fever who was admitted to the hospital with an influenza-like illness. The patient experienced severe conditions of COVID-19 and dengue fever with shock followed by disseminated intravascular coagulation. The standard of COVID-19 care was given coupled with fluid resuscitation and blood transfusion. The pitfalls of this case are how to differentiate the clinical manifestation of dengue fever in a patient with confirmed COVID-19; the difficulty to monitor the dengue course of illness of the patient in the COVID-19 isolation room; and to differentiate the severe dengue from the multisystem inflammatory syndrome-C when the patient was in critical condition. The infant recovered without sequale, but the management of new probable cases must be improved more thoroughly, especially during dengue peak period in tropical and developing countries such as Indonesia.