Bilateral mastoiditis has the following symptoms: I. In the recovery period of acute suppurative otitis media, about 3-4 weeks of the disease, all kinds of symptoms do not continue to reduce, but rather aggravate, should be considered to have the possibility of acute mastoiditis, such as tympanic membrane perforation, the ear pain does not reduce or once reduced and then aggravated, hearing does not improve but rather declined, the ear flow of pus does not reduce but rather increase, the systemic symptoms aggravated, the temperature is again elevated. Second, the mastoid skin is swollen and flushed, and the posterior fossa of the auricle disappears. Third, redness and swelling of the upper posterior wall of the bony external auditory canal, collapse, hemorrhage of the tympanic membrane, and the flaccid part may be puffed out.