Pus in the ear is a common symptom of ear disease, and in the case of otitis externa, there may be watery discharge. In the case of otitis externa, watery discharge may be present. When pus is present in the ear, attention should be paid to the nature, amount and odor of the pus for identification. When you find the symptoms of ear discharge, you should go to the hospital for examination in time to avoid delaying the treatment. Then how to conduct the examination? 1. Ask for medical history: otitis externa and external ear canal boils often have ear pain first and then overflow, with severe and persistent ear pain, while external ear canal boils have less ear pain after the outflow of pus; if there is ear itching without ear pain, it is mostly external ear canal eczema; cerebrospinal fluid ear leakage mostly has a history of cranial trauma or surgery; if there is ear pain and fever first, followed by pus and blood from the external ear canal, acute purulent otitis media should be considered; intermittent, recurrent or Intermittent, recurrent or persistent external ear canal pus flow with hearing loss is seen as chronic suppurative otitis media. Middle ear cancer often has a history of chronic purulent otitis media, with blood in the secretion and increased deafness, accompanied by ear pain and facial paralysis. 2. Physical examination: Pay attention to the nature, color and odor of the secretion. Plasmacy or purulent secretions mixed with blood are mostly acute purulent otitis media or external ear canal boils; cerebrospinal fluid ear leakage is a persistent, colorless and transparent watery liquid, which can be light red when mixed with blood but does not coagulate; cholesteatoma otitis media has a small amount of pus but has a strange odor; the secretions of tuberculous middle ear mastoiditis have a special fishy odor. Also note whether there are foreign bodies, cerumen plugs, cholesteatomas, and neoplastic organisms in the external ear canal, whether the skin is congested and swollen, and whether there are fistula openings. The tympanic membrane should be examined for blisters and perforations, and the tympanic chamber should be examined for masses and cholesteatomas, and the mastoid area should be examined for redness, swelling, and pressure pain. Laboratory tests: X-ray or CT examination should be performed if middle ear mastoid lesions are suspected; the sugar content of fluid should be checked and skull base X-ray examination should be performed if cerebrospinal fluid ear leakage is suspected; biopsy should be performed early if new organisms are found in the middle ear. Bacterial culture and drug sensitivity test should be performed for purulent secretions.