ObjectiveTo realize the isolation status of fastidious bacteria causing respiratory tract infection and antimicrobial susceptibility of fastidious bacteria to cefditoren pivoxil as well as the other 9 antimicrobial agents, so as to provide reference for clinical treatment.Methods Fastidious bacteria isolated from sputum of patients with respiratory tract infection during the year of 2005, 2007, 2008, and JanuaryJune in 2010 were collected. Antimicrobial susceptibility of fastidious bacteria were tested with KirbyBauer method recommended by Clinical and Laboratory Standards Institute (CLSI). ResultsA total of 462 isolates were isolated from 438 patients, βlactamaseproducing rate was as follows: Haemophilus influenzae (HI) 23.62% (30/127), Haemophilus parainfluenzae (HP) 2.51%(5/199), Moraxella catarrhalis (MC) 41.58% (42/101), penicillinresistant Streptococcus pneumoniae (SP) isolates was not found. The susceptibility rate (SR) of HI, HP, MC, and SP to cefditoren pivoxil was 96.30%, 94.36%, 100.00%, and 100.00%, respectively;The SR of HI and HP to cefotaxime, cefuroxime, cefaclor and cefazolin was 83.59%-93.33%, SR to amoxicillin/clavulanic acid was 91.67% and 88.21% respectively; SR of MC and SP to amoxicillin / clavulanic acid was 100.00%; SR of HI to clarithromycin was 87.96%,SR of HP, SP and MC to clarithromycin was 34.29%-59.00%; SR of 4 kinds of fastidious bacteria to tetracycline was 22.86%-63.00%; The resistant rate of HI,HP and MC to trimethoprim/sulfamethoxazole was 54.63%-3.33%.ConclusionCefditoren pivoxil has strong activity against fastidious bacteria causing respiratory tract infection; in order to reduce the emergence of drugresistant strain, clinicians should choose antimicrobial agents according to antimicrobial susceptibility test results.