Subdural hematomas constitute rare causes of secondary Parkinsonism in elderly. Subacute or chronic subdural hematomas occur in the elderly following minor head trauma or even without a remarkable history of trauma. A 69-year-old woman admitted with a rapidly progressive acute-onset hemiparkinsonism on the left side of her body. She denied any precipitating event before the onset of her symptoms, and her medical history was unremarkable. The anti-Parkinsonian therapy showed no benefit, but gradually worsening of the symptoms was observed. Her brain magnetic resonance imaging revealed a large subacute-chronic subdural hematoma on the right side with a mass effect on the basal ganglia structures, contralateral to her symptomatology. On thorough questioning, she confessed to having fallen out of the bed at night almost four weeks ago, three-weeks before the onset of her symptomatology. She had no complications associated with this fall and merely remembered this event. She denied any history of rapid eye movements (REM) sleep behavior disorder. The anti-Parkinsonian treatment was discontinued; the subdural hematoma was evacuated via burr hole drainage surgery. Her symptoms disappeared instantly after the surgery, with a normal neurologic examination one week after the surgery.