There are many causes of tinnitus. Subjective tinnitus is a type of tinnitus for which no cause can be found clinically, and it is characterized by the patient’s ability to feel the tinnitus himself, so it is called subjective tinnitus. Tinnitus can be caused by a number of systemic diseases, such as anemia, hypertension, hypothyroidism, kidney disease, etc. Objective tinnitus, which is not only felt by the patient but also heard by the examiner, is called objective tinnitus, such as vascular tinnitus, which is characterized by a vascular murmur around the ear and can disappear when the carotid artery is compressed. There are also some myogenic tinnitus, which are mostly caused by clonus in the palate or tympanic muscles. In conclusion, there are many causes of tinnitus and different methods of classification.