Some moms and dads find that their babies have constant tears in one eye. It should be handled according to the cause. 1, dacryocystitis: newborns often runny eyes are mostly caused by the blockage of the tear duct, dacryocystitis, usually within 4 months to recover on their own. If it does not recover within 4 months, the dacryocystitis should be actively treated. If there is no redness, swelling, heat and pain in the corner of the eye and the root of the nose, it is considered to be chronic dacryocystitis, which manifests itself as tearing, with more secretions in the eyes, and a large amount of purulent or plasma secretions can be seen gushing out of the tear ducts from the tear ducts by squeezing the area of the affected tear sacs, and the affected tear ducts are not flushed. It is recommended to use antibiotic eye drops and flush the tear ducts first. If it can not be cured, can wait for the baby a little bit older for tear duct exploratory surgery. 2, inverted eyelashes: small children’s nose is not fully developed, coupled with the cheeks fat, squeeze the lower eyelid inward, eyelashes will be attached to the black eyeball (cornea). In this case, the eyelashes stimulate the cornea, the baby will feel a foreign body sensation, pain and cause tears, repeatedly rubbing the eyes with the finger secondary infection will produce eye boogers. There is no need to be anxious in this case, because the child’s eyelashes are relatively soft, and the damage to the black eyeball (cornea) is limited. Appropriate use of anti-inflammatory drops and corneal epithelial protection gel can be. Generally, as the child’s nasal bone slowly develops, the symptoms of inverted eyelashes will slowly reduce, and the tearing will be relieved after the irritation to the eyeball is reduced. 3, infectious conjunctivitis: when the baby fever, cold, runny nose, cough, easy to appear more eye boogers, yellow color, accompanied by the phenomenon of tears. This is mostly due to the causative agent of upper respiratory tract infections, rubbing the eyes when the child wipes the nose and coughs, leading to bacterial, Chlamydia trachomatis or viral infection of the conjunctiva or cornea. In such cases, parents are advised to take their children to the internal medicine department to control the upper respiratory tract infection, and to encourage their children to wash their hands regularly and not to rub their eyes or nose with their fingers. You can use drugs such as Tobax eye drops, Coloplast eye drops, or Ricocin eye gel to kill the virus locally. At the same time, reduce the public places activities, do not take children to kindergartens, schools, early childhood education classes, etc., to avoid cross-infection. 4, allergic conjunctivitis: children often come into contact with a variety of substances in nature (such as dust, dirt, animal fur, pollen, chemical fiber fabrics, etc.), these substances are prone to allergies and cause conjunctivitis, known as allergic conjunctivitis. This is caused by an allergic reaction of the mucous membrane on the surface of the eye to specific allergen particles suspended in the air. The first step is to stop the stimulation of allergic substances, reduce the time of outdoor grass, playground activities, reduce the contact with dogs and cats, and reduce the intake of seafood, fish and shrimp. In the acute stage, we can use steroids and anti-allergy eye drops for short-term treatment, and then switch to non-irritating natural plant desensitizing factors for complete desensitization after the condition is stabilized.