Unilateral tinnitus may be caused by cerumen impaction, Meniere’s disease, secretory otitis media and other diseases. 1. Cerumen embolism: If the external auditory canal is not completely blocked, there are no symptoms, and there may be local itching sensation. When cerumen completely blocks the external auditory canal, the ear may be stuffy and uncomfortable, accompanied by hearing loss, and sometimes there may be tinnitus in line with the pulse. 2. Ménière’s disease: the etiology of this disease is still unclear, studies have shown that it may be related to lymphatic absorption disorders and mechanical obstruction of lymphatic vessels. Secondly, it may also be related to heredity, viral infection and ischemia of the inner ear. Patients will experience symptoms such as vertigo, hearing loss and tinnitus, which may manifest as unilateral tinnitus. 3. Secretory otitis media: The occurrence of this disease is related to the obstruction of the Eustachian tube, pathogenic microbial infection, immune response, dental malocclusion, gastroesophageal reflux and other causes. The dysfunction of the Eustachian tube leads to negative pressure in the middle ear, and even the production of fluid, resulting in unilateral tinnitus, occlusion in the ear, hearing loss and other symptoms. In addition, unilateral tinnitus can also be caused by sudden deafness and diseases such as acoustic neuroma. The patient needs to go to the hospital to clarify the exact cause.