ObjectiveTo investigate the differences of bacteriological characteristics between adults and children with chronic secretory otitis media (SOM) via detecting the prevalences of six kinds of bacteria including Alloiococcus otitidis, Streptococcus pneumonia, Haemophilus influenzae, Moraxella catarrhails, Staphylococcus aureus, and Streptococcus viridans in the middle ear fluid (MEF) and nasopharyngeal secretion (NS).MethodsThe prevalences of Alloiococcus otitidis, Streptococcus pneumonia, Haemophilus influenzae, Moraxella catarrhails, Staphylococcus aureus, and Streptococcus viridans were investigated by polymerase chain reaction (PCR) in the MEF and nasopharyngeal swabs of all the patients.Results① With similar bacterial spectrum, the bacterium detection rates in adults and children were 91.30% (63/69) and 88.25%（63/69）respectively. The difference was statistically insignificant (P>0.05).② In the MEF of chronic SOM patients, two or more kinds of bacteria could be detected. The prevalence in children was higher than that in adults, and the difference was statistically significant (P<0.05). ③As for the bacteria detected in MEF, Streptococcus pneumoniae and Staphylococcus aureus were the most frequent pathogens in children, Staphylococcus aureus was the most common in adults. ④ In the MEF, the detection rate of Streptococcus pneumonia in children was higher than that in adults (P<0.05), while the prevalence differences of the other 5 bacteria between children and adults were all statistically insignificant (all P>0.05). ⑤In children with SOM, the detection rates of Streptococcus viridans, Haemophilus influenzae, Moraxella catarrhails in NS were higher than those in MEF with statistical significant differences (all P<0.05). The detection rates of Alloiococcus otitidis, Staphylococcus aureus and Streptococcus pneumonia in NS were similar to those in MEF, their differences were all statistically insignificant (all P>0.05).⑥ In adults with SOM, the detection rate of Streptococcus viridans in NS was higher than that in MEF (P<0.05), while the differences of detection rates of the other bacteria in NS and MEF were all statistically insignificant (all P>0.05).ConclusionMultiple bacterial infections in children with SOM are more common than those in adults.