Left maxillary sinus cyst, may be related to the inflammatory stimulation within the maxillary sinus, resulting in blockage of the glandular ducts or sinus orifice caused by the cyst will not subside on its own if left untreated. However, if the cyst is small in size, it can be treated without any special treatment. If it is large in size and accompanied by uncomfortable symptoms, it needs to be treated by surgery. Maxillary sinus cyst, is a benign lesion, slow-growing, if the size of the cyst is small, usually no obvious symptoms, can not be specially treated, usually does not affect the health, if the size of the larger and longer, may be ulcerated, accompanied by headache, head swelling, facial swelling and other symptoms, need to carry out a cystectomy surgery for treatment. Left maxillary sinus cyst, it is recommended to go to the hospital in time for diagnosis, treatment under the guidance of the doctor, pay attention to light diet, avoid spicy and irritating food, and pay attention to more rest.