A 4-year-old boy who was involved in a motor vehicle accident as a pedestrian and suffered blunt chest trauma was admitted to the emergency room. Unpredictable delayed ventricular fibrillation was diagnosed and treated successfully 2 h later. This case cannot be classified as commotio cordis as the ventricular fibrillation (VF) developed so long after the sustained chest injury. At the same time, other possible etiologies of VF such as cardiac pathology or electrolyte and metabolic disorders had been ruled out. Thus, an etiological link between the chest trauma and the subsequent VF could not be ruled out and is in fact plausible despite the late onset.