In most cases, subdural hematoma (SDH) is regarded as a complication of head injury and nontraumatic causes are rare. Moreover, spontaneous chronic SDH in child or adolescent is very unusual. Here, we present the case of a healthy 14-year-old girl who was diagnosed as a spontaneous chronic SDH. The patient presented with severe headache following blurring of vision two weeks ago without any history of trivial head injury. Computed tomography and magnetic resonance imaging depicted a chronic SDH. The cause of the hematoma was not established. After performing burr hole drainage of the hematoma, the patient made an uneventful recovery. We explore the potential risk factors and pathophysiology implicated in this condition. Possible pathogenic mechanisms of this unique case are discussed and a review of the pertinent literature is included.