Dengue is endemic in over 100 countries worldwide, predominantly in the subtropical and tropical regions and the incidence has been increasing globally. Patients with severe dengue may develop massive bleeding, disseminated intravascular coagulopathy and multi-organ failure. Bleeding may occur in various body cavities and muscles; however, bleeding in the retroperitoneal space is uncommon. We report a case of a 37-year-old gentleman who presented with a 4-day history of fever associated with chills and rigours. On Day 6 of illness, he complained of left lumbar and left iliac fossa pain which was aggravated by movement. A computed tomography angiography scan of the abdomen showed the presence of a retroperitoneal haematoma, left iliopsoas and quadratus lumbarum intramuscular haematoma with active bleeding and left abdominal wall muscles haematoma. His condition gradually improved after multiple blood transfusions and he gained full recovery. Spontaneous retroperitoneal haematoma is an uncommon complication of severe dengue infection. Early diagnosis based on high index of clinical suspicion using appropriate imaging will aid in prompt management of these cases and may prevent deaths.