Microorganisms were investigated in 44 patients with chronic otitis media (COM) and repeated otorrhea. The same species were isolated most frequently from those with repeated otorrhrea (24 of 44 cases). The species were Staph. aureus (10 caces), P. aeruginosa (9 cases), Staph. epidermidis (4 cases), and P. cepacia (1 case).For each species isolated from the same patient, similar sensitivity to antibiotics were observed. Therefore, we considered that reinfection by the bacteria existing in the body caused otorrhea in some cases.After NFLX was administered for MRSA infection in COM, Cephem antibiotics (CEZ, LMOX, etc) showed a recovery of sensitivity to Staph. aureus. We observed a superinfection by Methicillin-Cephem-Resistant Staph. epidermidis (MRSE) after antibiotics therapy for MRSA in COM.