The phenomenon of small pupil may be due to physiological reasons or pathological reasons, such as iridocyclitis, Horner’s syndrome, etc. Different treatment measures should be taken according to the different causes, such as general treatment, medication, surgical treatment, treatment of trauma and so on. 1. General treatment: if the body’s eyes are stimulated by bright light or eye fatigue, the pupil will appear physiological shrinkage phenomenon, which generally does not require special treatment, do a good job of scientific eye use, good eye care. 2. Pathological causes: medication or surgical treatment is needed, and if the pupil is small due to trauma, the trauma needs to be treated in time. (1) Drug treatment: iridocyclitis caused by protozoal infection, human immune dysfunction and trauma, etc., the phenomenon of pupil shrinkage occurs due to irritation, which can be treated with non-steroidal anti-inflammatory drugs such as acetaminophen. Acute cerebral infarction causing Horner’s syndrome should be treated with thrombolysis. (2) Surgery: Horner’s syndrome caused by oculo-sympathetic paralysis may also have small pupils, accompanied by ptosis and other symptoms, and should be treated according to different triggers, and surgery should be performed if necessary. (3) Treatment of trauma: If it is caused by trauma, the patient should be transported to the hospital for treatment of trauma under the guidance of emergency personnel. If the above symptoms occur and physiological causes are ruled out, it is recommended to consult the hospital in time to find out the cause of the disease and actively cooperate with the doctor for treatment.