Tinnitus in the left ear may be the result of sudden deafness, or it may be caused by an acoustic neuroma or hypertension, and tinnitus is often an early manifestation in the development of these diseases. However, tinnitus is caused by many reasons, generally can not be judged by tinnitus is the early sign of which disease. 1. Sudden deafness: the above causes may be associated with viral infections, autoimmune and circulatory disorders, which may be manifested as unilateral low hearing volume, tinnitus, dizziness and other clinical symptoms, of which tinnitus may be the first symptom, so tinnitus in the left ear may be an early sign of sudden deafness. 2. Auditory neuroma: mainly refers to the tumor originated from the section of the inner ear canal of the Ⅷ cerebral nerve, if the tumor volume is relatively small, it will induce unilateral tinnitus with low hearing volume, and a small number of them will manifest for a long time of deafness, so unilateral tinnitus may be the early signal of auditory neuroma. 3. Hypertension: If you suffer from cerebrovascular abnormality, it may lead to the expansion of anterior inferior cerebellar artery to compress the auditory nerve and induce unilateral tinnitus after the blood pressure is elevated, so tinnitus in the left ear may be the early reaction of hypertension in cerebrovascular disease. If tinnitus in the left ear occurs, it may also be Meniere’s disease, etc. It is recommended to observe closely, and consult a doctor in time for abnormalities and systematic examination for a clear diagnosis.