IntroductionBicycle handle bar injury occurs when the handlebar of the bicycle strikes to cause an impact on the body. This mechanism of injury is responsible for a significant number of thoraco-abdominal injuries in children with more than a third of them requiring surgical intervention.1 The most common among them involves intra-abdominal organ injuries,  traumatic abdominal wall hernias and bladder rupture.2–4 However, retroperitoneal hematoma has rarely been reported in bicycle handle bar injury.5 Bleeding into the space behind the peritoneal cavity, referred to as retroperitoneal hematoma, is an obscure and under diagnosed condition due to the late manifestation of signs and symptoms until significant blood loss has occurred.6 Here, we present a case of 12 years old boy brought to the emergency department with the alleged history of bicycle handle bar injury who underwent emergency exploratory laparotomy that revealed massive retroperitoneal hematoma secondary to mesenteric/ vascular injury with intra-peritoneal extent.