Sinusitis is always tearing up, which may be related to the spread of inflammation and conjunctivitis, the blockage of nasolacrimal ducts and overflow of tears, and allergic factors secondary to conjunctivitis. 1. Conjunctivitis caused by the spread of inflammation: If the inflammation of sinusitis spreads, it may cause bacterial conjunctivitis, which will not only cause tearing, but also symptoms such as itching, redness and swelling of the eyes, and increased secretion. 2. Nasolacrimal duct blockage leads to tearing: If sinusitis causes blockage of the nasolacrimal duct, tearing and swelling of the lacrimal sac will often occur, resulting in constant tearing of the eyes. 3. Allergic factors secondary to allergic conjunctivitis: If sinusitis is caused by allergies or if you are allergy-prone, when you come into contact with allergens, allergic conjunctivitis may occur, and you will also have sinusitis that causes constant tearing. Therefore, sinusitis is always running eyes should be timely medical care, to clarify the specific causes, and then develop a suitable treatment program.