Purpose: To describe successful control of outbreak of ESBL producing K. pneumoniae in neonatal intensive care unit. Methods: The 9 K. pneumoniae isolated from blood (7), urine (1), eye discharge (1) culture. The 5 cases with blood isolated were all occurred in infants with less than 1,500 g body weight. Intervention activities included hand hygiene, using maximal sterile barrier precaution during central venous catheter insertion, monitoring of medical staff`s performance of the contact precaution guidelines, and regular environmental cleaning and incubator disinfection. Especially, our study found the serious problem that the omnibedTM incubators are not replaced regularly to minimize intervention for very low birth weight infants. Results: It was recommended to replace a used omnibedTM incubator with an antiseptic one every week. Before the implementation of infection control, K. pneumoniae infection rate 6.29 per 1,000 patient-days. After the implementation, 2.02 per 1,000 patient-days January 2011 and 0 infection after February 2011. Conclusion: Our study demonstrates the importance of hand hygiene, aseptic technique, isolation precaution and environmental cleaning and disinfection of medical equipment. Especially, this outbreak was controlled by emphasizing the control of incubator as environmental reservoirs using for premature baby.