Obstruction of nasolacrimal duct is common. When irrigation and massage are still ineffective, lacrimal duct probing can be done. The operation is to use a hollow lacrimal probe under local anesthesia, with a plastic tube or nylon thread in the hollow, penetrate into the nasal cavity along the nasolacrimal duct through the lacrimal sac, then pull out the probe and leave the plastic tube in the lacrimal passage. Pull out the plastic pipe in about two months. Antibiotics can be used to prevent infection after operation, and there is no scar left in this operation.