A 44-year-old female fainted when she went to the bathroom at midnight. There was abruise over her right cheek when she regained consciousness. The patient had no headacheor neurological defects on physical examination. The computed tomographic (CT) scan ofthe brain showed a chronic subdural hematoma over the right fronto-parietal lobe 12 weeksafter the fainting episode. She took a modification of xuˇe fˇu zhú yˉu tˉang ( , XZT,House of Blood Stasis-Expelling Decoction) for moving the blood and transforming stasis.The subdural hematoma disappeared 2 months after she began taking the formula. Themechanisms of XZT to treat chronic subdural hematoma might be (1) regulating the permeabilityof hematoma capsule to prevent recurrent bleeding, and (2) promoting the microcirculationaround the hematoma to accelerate resolution of subdural collection.