The ear keeps running can be caused by purulent otitis media, external ear canal eczema, cerebrospinal fluid ear leakage and other factors. 1. Suppurative otitis media: acute suppurative otitis media is caused by bacterial infection and other factors, fever, chills and other systemic symptoms, ear pain, hearing loss and tinnitus, perforation of the tympanic membrane can be seen in the pus oozing out of the ear, and there is a flow of water. 2. Eczema of the external auditory canal: Eczema of the external auditory canal is an allergic polymorphic dermatitis that occurs in the external auditory canal. It is mainly characterized by local symptoms, such as itching, flaking, etc., and can be accompanied by different degrees of secretion exudation and scabbing, which can lead to the manifestation of running water in the ear. 3. Cerebrospinal fluid ear leakage: Cerebrospinal fluid ear leakage is caused by deformity, trauma, inflammation, tumor and other factors, which can be manifested as fluid accumulation in the tympanic cavity or outflow through the perforated tympanic membrane and the eustachian tube, resulting in the manifestation of running water in the ear. When the ear has been flowing should be timely consultation, diagnosis is clear, under the guidance of specialists to actively carry out appropriate treatment.