We report a case of spontaneous calf muscle haematoma, formed during the recovery phase of dengue haemorrhagic fever, which, to the best of our knowledge, has never been encountered before. A 45-year-old man presented with features of severe dengue and got admitted to our intensive care unit. He was treated with intravenous fluid therapy and supportive measures, and gradually improved, initially. However, during the recovery phase, he suddenly developed painful left calf, which was found tender, hot and swollen on physical examination. Colour Doppler ultrasound revealed left calf haematoma. As the patient rapidly developed local compartmental syndrome, surgical evacuation of the haematoma followed by urgent fasciotomy was performed. He recovered without further complication and was discharged home. At follow-up after 2 months, he remained well.