The uncontrolled shaking of the left hand of the elderly may be physiological hand tremor, but also may be caused by idiopathic tremor, Parkinson’s disease and other causes. 1. Physiological hand tremor: overwork, mental stress, emotional excitement, etc., will lead to the symptoms of left hand tremor in the elderly, after resting, it usually improves on its own and does not require special treatment. 2. Idiopathic tremor: probably related to genetic factors, the left hand may shake involuntarily, especially when nervousness and over fatigue, the symptom is more obvious, usually does not have too much impact on daily life. If it is too serious, it can be treated with medication or surgery, which needs to be done under the guidance of a doctor. 3. Parkinson’s disease: a neurodegenerative disease, one of the clinical manifestations of stationary tremor, which is mainly characterized by the appearance or obvious at rest, reduced or stopped during random movements, aggravated by nervousness, and disappeared after going to sleep. If the old man’s left hand has been shaking for a long time, it is not excluded that it is stationary tremor. In addition, cerebral arteriosclerosis, endocrine dysfunction, drug intoxication and other causes can also lead to uncontrolled hand tremor. If the uncontrollable shaking of the left hand in the elderly excludes physiological causes and is accompanied by other abnormal manifestations, it is recommended to consult a doctor for examination and treatment to avoid aggravation of the lesion.