Abstract: Objective To investigate the nasopharyngeal carriage rate, serotype distribution and antimicrobial resistance of Haemophilus influenzae among children visiting an outpatient department in Beijing Children’s Hospital with upper respiratory infection from March 2013 to February 2014.Methods We selected 100 Hi isolates randomly. The serotypes were determined by the latex-agglutination and the antibiotic susceptibility was tested by E-test method. The serotyping and antimicrobial resistance data were analyzed with the WHONET 5.3 software. The χ² test, performed with the SPSS software v. 16.0 (SPSS Inc. USA), was used for statistical comparisons. A two-tailed cut-off of P<0.05 was deemed to indicate statistical significance.Results The nasopharyngeal carriage rate for Haemophilus influenzae was 9.2% (271/2930), major in April to June (19.5%, 20.6% and 24.5%). The number of boys was larger than that of girls’ (χ²=7.219, P<0.05), and mostly aged 4~6 years old (＞10%). All of the isolates were non-typable. The susceptibility to tetracycline, chloramphenicol, amoxycillin/clavulanate, and cefuroxime were 97.0%, 96.0%, 91.0% and 82.0%, respectively. The non-susceptibility to penicillin was 35.0%. The carriage rate of beta-lactamase was 23.0%.Conclusion About 9.2% of children with upper respiratory infection were nasopharyngeal colonized by Haemophilus influenzae. The infection is closely related with age, gender and season in Beijing. The non-susceptibility to penicillin was high, and the beta-lactamase positive rate of Haemophilus influenzae was high and increased rapidly.