The causes of involuntary hand shaking include physiological causes and disease factors. Physiologic causes include exertion, emotional stress, and so on. Disease factors include idiopathic tremor, Parkinson’s disease, hyperthyroidism, hypoglycemic reaction, etc. 1. Physiological factors (1) Exhaustion: When the hands are overworked, involuntary tremor may occur when doing fixed movements, which will gradually disappear after rest. (2) Emotional excitement: when the patient is excited, the sympathetic nerves are excited, and the symptoms of involuntary shaking of the hands will appear, and will return to normal after the emotions are stabilized. 2. Disease factors (1) Idiopathic tremor: this disease is mainly related to genetic factors, and the hands will shake involuntarily at the onset of the symptoms. (2) Parkinson’s disease: this is a degenerative disease, the onset of the hand will appear involuntary shaking symptoms, and accompanied by muscle tone, motor retardation. (3) Hyperthyroidism: At the onset of the disease, symptoms such as hand shaking occur due to increased basal metabolism. (4) Hypoglycemic reaction: when the patient’s blood sugar is lower than normal, the symptoms of hand shaking can also appear.