Extended-spectrum beta-lactamase-producing E. coli were recovered from 16 patients in a neurosurgical intensive care unit; surveillance cultures revealed that the organism could be transmitted through the contaminated environment and the hands of health care personnel. All isolates from the patients, environment, and health care personnel showed the same pulsed-field gel electrophoresis pattern. Isoelectric focusing, PCR analysis,and sequencing demonstrated that this E. coli harbored CTX-M-15 and OXA-30 beta-lactamases that were transferred by conjugation. This is the first report of nosocomial transmission caused by E. coli that harbor the combination of CTX-M-15 and OXA-30. This can be a threat because the organisms can hydrolyze cefotaxime, ceftazidime, and cefepime.