The following diseases are common in the flow of clear water from the ear: 1. Eczema of the external ear canal, manifested by itchy ears and exudate, which can be colorless or yellowish. 2. Cerebrospinal fluid ear leakage, where the patient has a clear history of cranial trauma, which can be seen during clinical examination, with a perforated eardrum or a broken ear canal wall appearing as a flow of clear water. 3. Otitis media, where the eardrum is perforated and the inflammatory infection is not very heavy, can manifest as a flow of clear water inside the ear. This disease is not very common, but it does occur. If there is clear water flowing from the ear, it is recommended that the patient go to an ENT clinic to check the condition of the ear canal, take a detailed medical history, do an electronic tympanic membrane image examination, etc. for a comprehensive judgment, and if necessary, improve the CT to make a comprehensive judgment as to which disease the patient actually belongs to.