Maxillary sinus cysts need to be differentiated from maxillary sinus cancer, chronic maxillary sinusitis, and maxillary cysts. It is recommended to go to ENT department of hospital for further examination to make a clear diagnosis. 1. Maxillary sinus cancer: Early stage patients do not have obvious clinical manifestations. When the cancer invades the inner wall of maxillary sinus, it can produce nasal symptoms such as nosebleed and nasal congestion. When the cancer invades the bottom wall of the mandibular sinus, it can produce symptoms such as grinding pain and loose teeth. CT or MRI of the sinus can clarify the size of the tumor and the site of invasion. 2. Chronic maxillary sinusitis: patients except nasal congestion, runny nose, headache, smell obstruction and other symptoms. The diagnosis can be clarified according to the medical history, nasal endoscopy and sinus CT examination. 3. Jaw cysts: they can be divided into odontogenic cysts and non-odontogenic cysts. Early asymptomatic, cysts can appear after the enlargement of the cheek bulge deformity, nasal congestion, displacement of the eyeballs, visual impairment, recurrent infection of the oral mucosa, etc. CT or MRI examination results can distinguish between odontogenic cysts and maxillary sinus cysts. Patients suspected of having maxillary sinus cysts are advised to visit the ENT department of the hospital as soon as possible to further improve the examination so as not to delay the treatment.