OBJECTIVE To study the risk factors of extended-spectrum beta-lactamases(ESBLs) producing bacteria infection in children,and provide reference to prevent and control the prevalence of bacterial strain of ESBLs.METHODS In a case and control studys the samples were selected randomly from 2007 to 2009 in the Children′s Hospital of Shanxi Province.The samples of case and control were all 100.RESULTS ?2 Test showed that boy and baby,previous history,pneumonia,medical ward,hospital infection and using antibiotics before admission to hospital were the risk factors;t-test showed that high white blood cell and neutrophil were the protective factors;Logistic regression showed that boy,previous history,hospital infection,using antibiotics before admission to hospital and medical ward were the risk factors and anal tube was a protective factor.CONCLUSIONS Increasing the rate of bacteriological test to the children who have the relative risk factors is very important to prevent and control the prevalence of ESBLs strain.