Objective    To explore the clinical features

drug resistance and prognosis of moraxella catarrhalis infection in order to guide the rational administration.     Methods    Sputum from 10 442 children with lower respiratory infection in our hospital were cultured. Susceptibility test and beta-lactamase were carried out to isolated moraxella catarrhalis. Then clinical features and prognosis of the infection were analyzed. Other respiratory pathogens were detected.     Results    Moraxella catarrhalis infection were popular in infants

frequently accompanied with other pathogens

and the germ was commonly isolated in winter. Its beta-lactamase positive rate was 63.4％. And its drug resistance rate to ampicillin and sulfamethoxazole

were 46.2％ and 43.4％ respectively

and to oxef and enzyme inhibitor containing antibiotics were less than 5.0％.     Conclusion    The infection of moraxella catarrhalis in children with respiratory infection is closely related with season and age. Its beta-lactamase positive rate is low. The rate of drug resistance to ampicillin is high. It is necessary for us to monitoring drug resistance and beta-lactamase positive rate of moraxella catarrhalis to guide the rational administration.