Yellow water from the left ear mainly occurs with the following diseases: the first one, eczema of the external ear canal. In addition to yellow water, the patient may have itchy ears, which is mainly caused by allergic factors and is related to the patient’s eating or contact with allergens, and generally does not affect hearing very much. The second type, chronic suppurative otitis media. It is mainly a yellow purulent discharge from the ear, which may be accompanied by foul smell or blood or something like that. Clinically, for patients with yellow discharge from the ear, it is recommended to go to the ENT department for an otoscopy. If swelling of the ear canal is seen, the ear canal is pale or the ear canal is crusted with yellowish water, it suggests that it may be eczema of the external ear canal. If the swelling of the ear canal is seen to be not very obvious and the tympanic membrane is seen to be perforated with a lot of purulent discharge coming from inside the tympanic membrane, the patient is considered to be suffering from otitis media, and bacterial culture of the yellow discharge can also be done.