Objective To find out the antimicrobial sensitivity characteristics of bacteria from CAPD-related peritonitis patients in an attempt to optimize the clinical therapy. Methods We collected 79 episodes of peritonitis from 50 patients between January 2006 and August 2010. We then analyzed the changes of bacterial spectrum and the differences of bacterial resistance to antibiotics. SPSS 13.0 software was used for the analyses. Results In the 79 peritonitis episodes, gram-positive organism infection was found in 34 episodes (44.3%), gram-negative organism infection in 17 episodes (21.5%), fungus infection in one episode (1.3%), mycobacterium tuberculosis infection in one episode (1.3%), and bacterial culture was negative in 25 episodes (31.6%), with the positive culture rate of 68.4%. In staphylococcus strains, the percentage of resistance to Penicillin and Ampicillin was >90%, that of resistance to Cefazolin was 30.0%, and that of resistance to Cephradine was 0%. Methicillin-resistant staphylococcus aureus (MRSA) was not found in this study. In streptococcus strains, the percentage of resistance to Streptomycin, Levofloxacin and Vancomycin was low. In gram-negative organisms, most of them were sensitive to Amikacin and Imipenem/Cilastatin, but the percentage of resistance to Ceftazidime was 17.6%. Conclusion In addition to the traditional antibiotics of Cefazolin and Ceftazidime, Cephradine combined with Amikacin are preferable for the treatment of CAPD-related peritonitis.