Causes of chronic subdural hematoma include head trauma, long-term use of anticoagulants, and vitamin C deficiency. Chronic subdural hematoma has a longer course and progresses slowly, usually for about a month, and manifests itself as a chronic collection of blood between the arachnoid membrane and the dura mater, and most often occurs in the elderly. When there is a minor head trauma, the cerebral blood vessels may appear smaller damage, if the wound healing is slow can cause chronic bleeding, blood accumulation between the arachnoid membrane and the dura mater, the formation of hematoma. A small number of patients may have no obvious history of head trauma, but long-term use of anticoagulant drugs can lead to decreased coagulation ability, prone to cerebral vascular seepage, causing chronic hemorrhage. In addition, vitamin C deficiency caused by malnutrition can cause scurvy, which in turn can cause chronic subdural hematoma. There are many other causes of chronic subdural hematoma, and it is recommended that patients seek timely medical treatment and standardized treatment.