Tears in infants may be caused by environmental stimuli, dacryocystitis, allergic conjunctivitis and other reasons. 1. Environmental stimulation: Infant tearing may be caused by environmental stimulation, such as infants in a cold environment, the cold air will stimulate the eyeballs to cause tearing. If the baby is in a poor air environment, it can also irritate the eyeballs and lead to tearing. 2. Dacryocystitis: Dacryocystitis can also cause tearing in infants, and sometimes there is more eye discharge, mainly due to the tear sac is stimulated by inflammatory factors. This disease is mainly due to the development of the infant’s lacrimal sac is not sound, the tear duct is blocked caused by. 3. Allergic conjunctivitis: contact with allergens can lead to symptoms such as allergic conjunctivitis in infants. It can cause redness of the eyes, itching, tearing and pain in the eyes. Infants with chronic tearing should be examined in the hospital and treated for the cause, so as not to affect the development of the eyes.